Engaging in open innovation: The mediating role of work engagement in the relationship between transformational and transactional leadership and the quality of the open innovation process as perceived by employees

Abstract

This study contributes to the literature on open innovation by addressing the scarcity of individual-level literature and insight into the human side of open innovation. Specifically, it examines the relationships between transactional and transformational leadership on the one hand and the quality of the open innovation process as perceived by employees on the other, and whether these relationships are (partly) mediated by employees’ work engagement. Hypotheses were tested using partial least squares structural equation modelling analysis on a bootstrapped sample (n = 173) of employees in various organizations. Transformational leadership was shown to have a positive direct and indirect relationship with open innovation, partly mediated by engagement. Additionally, this study provides guidance for managers on how to enhance the employee’s perspective on the open innovation process through transformational leadership behaviour and work engagement.

Keywords

employee engagement equation modelling open innovation simultaneous transactional leadership transformational leadership

Introduction

Innovation has become an increasingly important factor for organizations to survive in contemporary dynamic and complex business environments (Chesbrough, 2003b). Innovation can be viewed as an organizational process, often initiated by organizations’ internal Research and Development departments, which comprises three main elements: idea generation, referring to the ability within an organization to create new ideas and solutions; idea promotion, referring to how and the extent to which new ideas are shared within other intra-organizational members; and idea realization, covering the implementation of an organization’s new ideas in product and service development (Hoch, 2013).

Recently, however, organizations have acknowledged that the traditional, mainly internally oriented, approach underlying the so-called ‘closed innovation’ process has become obsolete. This has led to the emergence of a new approach to innovation, coined ‘open innovation’. Open innovation offers organizations additional value by stimulating knowledge sharing within and across organizations (cf. Bahemia and Squire, 2010). Open innovation is based on the notion that innovative ideas are not concentrated in a handful of organizations or departments (Chesbrough, 2006) but are broadly distributed in the economic landscape (Chesbrough et al., 2014). In line with the trend of forming new strategic partnerships in terms of intra- and extra-organizational collaborations (Baum et al., 2000; Burns, 1978; Chesbrough, 2003a; Simonin, 1997), open innovation implies the systematic exploration, retention, and exploitation of knowledge inside and outside organizational boundaries (Lichtenthaler, 2011).

The majority of studies were conducted on the level of organizations and organizational networks (Chesbrough and Bogers, 2014) and largely focused on identifying the antecedents, processes and potential advantages and disadvantages of open innovation (Bogers et al., 2018). Scholarly evidence exists that organizations can benefit from the implementation of an open innovation strategy in terms of their profitability, their ability to deal with new market challenges (Bahemia and Squire, 2010; Gassmann et al., 2010) and their ability to discover new product combinations (Almirall and Casadesus-Masanell, 2010). While the literature presents a comprehensive outline of the potential gains of open innovation, they have only provided limited insight into how the open innovation process can be managed and led (Vanhaverbeke et al., 2014).

In spite of the growing attention that the topic of open innovation has received over the past few years (Huizingh, 2011), several aspects of this new paradigm have not yet been thoroughly investigated. In the light of this, there have been voices that call for more research on the organizational sublevel (Vanhaverbeke et al., 2014; West et al., 2014), stressing the need for a more elaborate examination of factors influencing individuals or groups that participate in the innovation process (Brunswicker and Chesbrough, 2018; West et al., 2006). In response to this call, recent studies have examined open innovation on a micro level. Salter et al. (2015), for example, focused on the role of individual-level openness and idea generation in R&D, and Rangus and Černe (2017) studied the relationship between leadership, openness and innovation performance. Furthermore, De Jong et al. (2018) looked into the relationship between authentic leadership, open innovation and culture. However, insight into employees’ perceptions within the open innovation process is still lacking. As West et al. (2014: 809) put it: ‘We still know little about how individuals who take up the open innovation role draw upon their networks to support them in this role’. This underlines the plea for paying more attention to employee-level mechanisms operating in the open innovation process (cf. Burcharth et al., 2014; Chesbrough, 2003a; West et al., 2006).

The need for more insight into factors affecting individuals’ perceptions of the innovation process has recently been re-emphasized by Brunswicker and Chesbrough (2018). They noticed that employees are still reluctant to engage in open innovation, despite its potential benefits. Possibly, individuals may experience reluctance to share their knowledge and ideas with others to develop new products from which also entities outside the borders of their own organization can benefit (West and Gallagher, 2006). In essence, however, the paradigm of open innovation calls for a workforce that is willing to share knowledge and ideas, both with intra-organizational and extra-organizational members (Bahemia and Squire, 2010; Hansen and Von Oetinger, 2001). In a similar vein, it has been shown that individuals’ openness to external sources of knowledge is curvilinearly related to their ideation performance (Salter et al., 2015). In other words, more insight into the employees’ perspectives towards the quality of the innovation process could be of tremendous importance, as it can contribute to gaining a deeper understanding of how open innovation should be organized and managed.

In view of the above, the present study focuses on factors in the perceptions of employees on the quality of the open innovation process. Leadership, for example, has been acknowledged to be an influential predictor in this regard (Latham, 2014; Rangus and Černe, 2017). In order to motivate individual employees to contribute to the more ‘ambiguous’ innovation trajectories, Chesbrough (2003a) suggested that organizations should reward their employees for their participation (Almirall and Casadesus-Masanell, 2010; West and Gallagher, 2006). It could be argued, therefore, that managers should display transactional leadership that emphasizes rewarding individual employees according to their performance, as this can extrinsically motivate employees to participate in the open innovation process and to deliver their best performance herein (cf. Burns, 1978).

Besides transactional leadership, however, it can also be argued that managers need to exercise transformational leadership, as this can intrinsically motivate their employees to engage in open innovation processes (De Jong et al., 2018; Hansen and Von Oetinger, 2001; Latham, 2014; Nedon, 2015), such that more creativity and innovation can be achieved (Nonaka, 1994). Transformational leadership can be defined as a process in which leaders and followers collaborate to achieve a higher degree of employee morale and motivation (Burns, 1978). Transformational leadership is believed to enable innovative work behaviour and creativity (Gumusluoglu and Ilsev, 2009), as it focuses on stimulating proactive behaviour (Den Hartog and Belschak, 2012) and creating results beyond the set expectations. Moreover, it has the potential to foster employees’ learning experiences and to encourage them to adopt new ways of thinking (Hater and Bass, 1988). In addition, transformational leadership is angled towards changing employees’ values, needs and beliefs in order to align these with one another and with the common goal of the organization (Kuhnert and Lewis, 1987). Consequently, employees may be transformed into leaders and leaders into moral agents (Burns, 1978), which may enhance the success of the open innovation process.

So far, however, insight into the underlying processes explaining the importance of employees’ perceptions within the open innovation process remains relatively obscure. Therefore, we argue that both transactional and transformational leadership (Barrick et al., 2015) are important for the quality of open innovation processes in organizations since both leadership styles have the capacity to motivate employees for and to feel engaged with the open innovation process, which stimulates their perception of the open innovation process. Employee engagement is defined by Kahn (1990: 694) as the ‘harnessing of organization members’ selves to their work roles: in engagement, people employ and express themselves physically, cognitively, emotionally, and mentally during role performances’. Employee engagement can, therefore, be associated with a higher level of self-efficacy (Schaufeli et al., 2001; Schaufeli and Salanova, 2007), which refers to individuals’ belief in their capabilities to organize and execute the courses of action required to produce given attainments (Bandura, 1997). Self-efficacy can also enhance employees’ capacity to create their own resources (Schaufeli and Bakker, 2004b; Shirom, 2003) and their ability to generate creative solutions in their work (Bakker et al., 2006; Gong et al., 2009). Generally, employees’ work engagement can be viewed as an important factor contributing to enhanced organizational performance (Medlin and Green, 2014). Some scholars have even described engagement as a vital component of an organization’s strategy to deal with the challenges that they face (Schaufeli and Salanova, 2007).

This study aims to contribute to the scholarly debates on open innovation, leadership and work engagement by examining how both transactional and transformational leadership relate to the quality of the open innovation process as perceived by employees, and whether these relationships are (partly) mediated by work engagement. The contribution to the scholarly and societal debates of the present study is fourfold.

First, the study addresses the lack of individual-level studies that is prevalent in today’s innovation literature (Bogers et al., 2018; Chesbrough and Bogers, 2014; West et al., 2014), and it aims to give more insight into how open innovation should be led and organized (Vanhaverbeke et al., 2014). By examining the relationships between transactional and transformational leadership on the one hand and the quality of the open innovation process as perceived by employees on the other, and by examining whether these relationships are (partly) mediated by employees’ work engagement, the study unveils the intra-organizational challenges of the open innovation process (cf. Bogers et al., 2018; De Jong et al., 2018; Frambach and Schillewaert, 2002; Rangus and Černe, 2017; Salter et al., 2015). In a similar vein, it provides a more comprehensive view on the individual components that determine firm-level openness (Bogers et al., 2018). Specifically, by examining the influence of different leadership behaviours in association with the engagement of employees, it provides insight into how employees view and experience the open innovation process and sheds light on what factors can motivate individuals to be more participative in this process (Brunswicker and Chesbrough, 2018).

Second, this study contributes to the currently ill understood human side of open innovation (Bogers et al., 2018; Gassmann et al., 2010). While employees are acknowledged to be one of the key components to successful open innovation (Chesbrough, 2003a), relatively little is known about the employees’ roles and perceptions of the open innovation process (Bogers et al., 2018; West et al., 2014). This study attempts to address this gap by examining the influence of employee engagement on the quality of the open innovation process as perceived by employees. Although work engagement can be viewed as an acknowledged influence within organizations and has often been related to leadership (Spreitzer et al., 2010; Zhu et al., 2009), empirical studies on the mediating role of work engagement in the relationship between leadership and employees’ perceptions of the open innovation process are scarce (Vanhaverbeke et al., 2014).

Third, aside from seeking to bridge the two aforementioned gaps in the literature, this study contributes to the debate on leadership, work engagement and open innovation. By discussing both intrinsic and extrinsic motivational mechanisms that are prompted by transactional and transformational leadership behaviours in relation to perceptions of individual employees on the quality of the open innovation process, this article complements recent studies which advocate gaining insight into the importance of leadership in the open innovation process (Ahn et al., 2017; Rangus and Černe, 2017).

Fourth, while primarily adding to the scholarly debate on open innovation, the present study also contributes to the associated management debate by analysing the mediating role of work engagement in the relationship between leadership and employees’ perceptions of the quality of the open innovation processes in which they participate (Brunswicker and Chesbrough, 2018; Giannopoulou et al., 2010). As collaboration (Baum et al., 2000) and innovation are two vital factors for organizations’ survival in present-day markets (Hoch, 2013), providing direction for managerial practice on how to successfully foster open innovation is of major importance (Brunswicker and Chesbrough, 2018).

The outline of this article is as follows. Based on the open innovation, leadership and engagement literatures, a set of hypotheses is developed. Next, the data and methodology are presented. Finally, the study results are analysed and discussed, followed by implications for theory and management practice.

Theory and hypotheses

The role of employees in the open innovation process is key (Chesbrough, 2003). Nevertheless, the number of studies that investigate the process from the individual’s perspective is limited (Bogers et al., 2018; Gassman et al., 2010; West et al., 2014), leading to a lack of insight into how individual components influence organizational performance (Bogers et al., 2017, 2018) and how open innovation should be led and managed (Vanhaverbeke et al., 2014). The quality of the open innovation process as perceived by employees entails the view of the employee towards how well the activities of idea generation, idea promotion and idea realization are incorporated in the teams in which they participate in order to engage in open innovation.

With regard to the latter, leadership has been acknowledged as an important predictor of open innovation (Rangus and Černe, 2017). By introducing transactional and transformational leadership behaviours, this study investigates both the extrinsic and intrinsic motivation of employees within the open innovation process. On the one hand, this combination should include transactional leadership, as this can potentially increase stability within teams through structure and incentives. By creating incentives in the form of contingent rewards for finding and using both internal and external knowledge (Almirall and Casadesus-Masanell, 2010; Chesbrough, 2003a), managers could counter employees’ reluctance to particulate in the open innovation process which might arise in the light of their perceptions that their innovative endeavours are also accessible to competitors (West and Gallagher, 2006). On the other hand, the balanced mix should include elements of transformational leadership, as this can positively influence participation in open innovation through motivating employees to be creative, to share knowledge (Gumusluoglu and Ilsev, 2009) and to foster autonomy (Bass, 1999; Burcharth et al., 2017). In a similar vein, Bass and Avolio (1994) acknowledged the influence of both leadership styles on employee performance, although they note that the influence of transformational leadership may be stronger.

Both transactional and transformational leadership behaviours can enhance employees’ work engagement through providing contingent rewards (Breevaart et al., 2014) and increasing their creativity, self-belief and optimism (Tims et al., 2011), respectively. When employees become more engaged in their work (Bakker et al., 2006), they also become more creative and confident (Bandura, 1997), and they display higher levels of self-efficacy (Schaufeli et al., 2001), all of which have the potential to generate a positive disposition and view on the open innovation process (Burchart et al., 2017; Gumusluoglu and Ilsev, 2009; Mumford and Licuanan, 2004). The proposed relationships will be elaborated in further detail below, in order to develop a set of hypotheses to be tested empirically in the present study.

Transactional leadership and the quality of the open innovation process as perceived by employees

Transactional leadership is often believed to foster efficiency and stability within teams (Brown et al., 1996), which may also apply to team processes in open innovation. Since transactional leadership focuses on rewarding employee performance (Pearce and Sims, 2002), it answers Chesbrough’s (2003a) plea to stimulate employees to participate in the open innovation processes by introducing performance reward systems, even when employees may be reluctant to share their knowledge and ideas with others outside their team (West and Gallagher, 2006). Hence, transactional leadership could motivate employees to participate in the creation, promotion and subsequent implementation of innovative ideas (Hoch, 2013). The literature provided by Chesbrough (2003a) suggests that open innovation would resonate specifically with the part of transactional leadership that relates to contingent rewards. Less evidence is shown with respect to the transactional leadership concept’s dimensions: active and passive management by exception. Both are characterized by reactive behaviour based on observations of employees’ work behaviour (Judge and Piccolo, 2004) and can be considered counter-intuitive when engaging in open innovative processes that essentially entail proactive practices (Hoch, 2013). Hence, this research is focused on the dimensions of the transactional leadership concept that are related to rewarding employees’ performance. In view of the need for rewarding employees’ input in order to motivate them to participate in open innovation processes (Chesbrough, 2003a), transactional leadership can be expected to be positively related to how employees perceive the open innovation processes in which they participate. The following hypothesis was developed:

H1: Transactional leadership behaviour positively relates to employees’ perceptions of the quality of the open innovation process.

Transformational leadership and the quality of the open innovation process as perceived by employees

According to the literature, transformational leadership behaviour has the ability to positively stimulate innovation and team effectiveness (Brown et al., 1996). Based on previous insights (Brown et al., 1996; Burns, 1978), it can be expected that transformational leadership can support employees to effectively operate within organizations that have implemented open innovation and that it can influence their perception of the process. This leadership style focuses on inspiring a higher degree of motivation and morale in followers (Burns, 1978) and fosters autonomy (Bass, 1999). Research by Burchart et al. (2017) has recently shown that autonomy is positively related to open innovation. Furthermore, taking into consideration the advocacy by Chesbrough (2003a) of collaboration with external parties in the open innovation paradigm, this notion is further supported by a study conducted by Joshi et al. (2009) which proposes that transformational leadership is particularly effective in dispersed teams, as it encourages collaboration and the creation of a common purpose. A study conducted by Gumusluogu and Ilsev (2009) endorsed this idea and indicated a positive relationship between transformational leadership and individual employees’ creativity and organizations’ innovative behaviour. Furthermore, empowering employees through individual consideration by actively using knowledge in the strategy of an organization (Gumusluoglu and Ilsev, 2009) is a way for leaders to enable innovation within their organization (De Jong et al., 2018). Based on this account, the following hypothesis was developed:

H2: Transformational leadership behaviour positively relates to employees’ perceptions of the quality of the open innovation process.

Work engagement and quality of the open innovation process as perceived by employees

Open innovation is a paradigm which strongly depends on the innovative behaviour and creativity (Chesbrough, 2003a; Mumford and Licuanan, 2004) of participants in the open innovation process. Following Nedon (2015), who stressed the importance of work engagement in open innovation processes, this implies that employees need to broaden their focus on available resources beyond the borders of their own organization (Chesbrough, 2003b). According to Schaufeli and Bakker (2004a), employees who are more engaged in their work are more dedicated to their work, more energetic, and more immersed into their work and related responsibilities. Work engagement can be defined as an active and positive work-related mental state, which is constituted into three subdimensions: dedication, vigour and absorption (Schaufeli and Bakker, 2004b). Dedication refers to the degree of involvement which an employee experiences at work and is characterized by a sense of significance, challenge and enthusiasm while being at work and could be achieved through coaching and support from leaders (Schaufeli and Salanova, 2007). Vigour refers to employees showing a high degree of mental resilience and energy when at work (Schaufeli and Bakker, 2004b). Absorption can be characterized by a high degree of concentration and contentment while being at work (Schaufeli and Bakker, 2004a). Previous studies have shown that work engagement has a positive relationship with organizational performance (MacLeod and Clarke, 2009), as engaged employees are more resourceful and creative in finding solutions (Bakker et al., 2006). In turn, multiple studies have described the relationship between enhanced creativity and higher levels of innovative behaviour among employees (Gumusluoglu and Ilsev, 2009; Mumford and Licuanan, 2004). Engaging employees might be especially important in open innovation contexts where it is difficult to track each individual employee’s contribution to the innovation process leading to product development (Almirall and Casadesus-Masanell, 2010). In other words, open innovation much depends on work engagement, which reflects individuals’ intrinsic motivation (cf. Schaufeli and Bakker, 2004b) to be more dedicated to their responsibilities at work. Subsequently, it can be argued that this intrinsic motivation also influences one’s perception of the open innovation process. Based on the account above, the following hypothesis was developed:

H3: Employees’ work engagement positively relates to their perceptions of the quality of the open innovation process.

Transactional leadership, work engagement and the quality of the open innovation process as perceived by employees

Although Nedon (2015) does not explicitly link leadership to work engagement in the context of open innovation, during the past decades multiple studies have indicated a positive relationship between utilizing contingent rewards in leadership and the attitudes and the way employees behave in their workplace (Judge and Piccolo, 2004; Podsakoff et al., 2006; Walumbwa et al., 2008). A study conducted by Breevaart et al. (2014: 157) stated that: ‘It appeared that transformational leaders and leaders who use contingent rewards contribute to a favourable work environment (i.e., higher autonomy and social support), while management by exception actively contributes to a less favourable work environment (i.e., lower autonomy)’. This is in accordance with Bass and Avolio (1995) who stated that the provision of contingent rewards can enhance employees’ motivation, once the desired goals and respective incentives are clearly defined. Based on Chesbrough’s (2003a) plea for implementing a reward system to support open innovation and on Schaufeli and Bakker’s (2004b) finding that an engaged workforce is more dedicated to their responsibilities, the following hypothesis was developed:

H4: Employees’ work engagement positively mediates the relationship between their perceptions of transactional leadership behaviour and the quality of the open innovation process.

Transformational leadership, work engagement and quality of the open innovation process as perceived by employees

Bakker et al. (2004) indicated that engaged employees are more likely to perform beyond set expectations. Bass (1998) claimed that transformational leadership also encourages employees to perform beyond the usual standards, and that it encourages motivation and intellectual stimulation (Burns, 1978; Pearce and Sims, 2002). Nedon (2015) found that specifically intrinsic motivators support the employees’ willingness to engage in open innovation. Multiple studies (Avolio et al., 2004; Joshi et al., 2009; Ozaralli, 2003) described influences of transformational leadership which support employees to be more involved in their work, more effective and more content. These findings correspond with the three subdimensions of the work engagement concept (dedication, vigour and absorption) as presented by Schaufeli and Bakker (2004b). Also Tims et al. (2011) indicated a positive relationship between transformational leadership and work engagement. Moreover, Salanova et al. (2011) indicated the mediating role of efficacy and work engagement in the relationship between transformational leadership and extra-role performance. In a similar vein, it can be argued that increased creativity that stems from employees feeling more confident (Bandura, 1997) and engaged (Bakker et al., 2006) could potentially stimulate open innovation (Gumusluoglu and Ilsev, 2009; Mumford and Licuanan, 2004). Based on these arguments, the following hypothesis was developed:

H5: Employees’ work engagement positively mediates the relationship between their perceptions of transformational leadership behaviour and the quality of the open innovation process.

Methodology

Sample

Data were gathered by utilizing an online questionnaire which assessed employee perceptions and experiences of leadership, the quality of the open innovation process and work engagement, respectively. The sample consisted of 280 respondents, of whom 173 were deemed valid to be included in the sample. Invalid responses were excluded from the sample on the grounds of being incomplete or because they were completed in an unrealistic time frame. As Chesbrough (2003a) indicated that open innovation is applicable across multiple industries, the respondents were drawn from multiple different departments and industries to ensure the heterogeneity of the sample. The survey was distributed to the respondents from 15 November 2016 to 29 November 2016, through the use of a personal network and an online marketing bureau. A descriptive analysis was conducted to obtain a more sophisticated view on the sample, which is presented in Table 1.

Table 1.

Descriptive overview of the sample.

Construct	Frequency	Percentage	Mean	Standard deviation
Gender
Male	84	48.60	5.26	0.09
Female	89	51.40	4.86	1.11
Total	173	100.00
Age
Under 21	6	3.50	4.81	0.59
21–24	33	19.10	5.14	0.64
25–34	46	26.60	5.40	0.75
35–44	19	11.00	4.82	0.96
45–54	32	18.50	4.17	1.29
55–64	32	18.50	4.90	1.11
65–above	5	2.90	6.10	0.43
Total	173	100.00
Education
High school	13	7.50	5.09	0.70
IVE	36	20.80	4.67	1.16
Bachelor of Applied Science	39	22.50	5.33	0.77
Bachelor of Science	27	15.60	5.15	0.94
Master’s degree	52	30.1	4.80	1.04
Other	6	3.5	4.69	1.50
Total	173	100.00

Measures

All constructs in the proposed model were based on reflective multi-item scales. The instruments used for this study consisted of measures for the research constructs as described in this section. As the interest of this article lies in measuring the general influence between these constructs, the combined subscales from which they are constituted were utilized.

Perceived quality of the open innovation process was measured by items adapted from Hoch’s (2013) validated innovation questionnaire which comprises six items. Prior to filling in the related questions, respondents were provided with an introduction to the concept of open innovation, which described the context of generating, promoting and realizing ideas that are derived from internal as well as external sources. Since open innovation involves a process of working together with others inside or outside the respondents’ organizations, the items explicitly referred to open innovation as teamwork (referring to those whom the respondents themselves considered (potential) participants in the open innovation process), even though these teams could be multiple and could vary over time. An example of an item for each of the corresponding subscales reflecting the three stages of the open innovation process (i.e. idea generation, idea promotion and idea realization) are the following: ‘Our team searches out new working methods and techniques’, ‘In our team, we make each other enthusiastic for innovative ideas’ and ‘After we implement ideas, we evaluate their utility’. A seven-point Likert-type scale was used where 1 represented strongly disagree and 7 represented strongly agree.

Perceived transactional leadership was measured by utilizing the Personal Reward and Material Reward scales (six items in total) in the transactional leadership questionnaire developed by Pearce and Sims (2002) with a seven-point Likert-type scale (1 representing strongly disagree and 7 representing strongly agree). An example item is the following: ‘My team leader will recommend that I am compensated well if I perform well’.

Perceived transformational leadership was measured by one scale which comprised five subscales as presented by Pearce and Sims (2002): performance expectations, vision, idealism, inspirational communication and intellectual stimulation. An example item is the following: ‘My team leader provides a clear vision of where our team is going’. A seven-point Likert-type scale was used where 1 represented strongly disagree and 7 represented strongly agree.

Work engagement was assessed with one scale which comprises three subscales: vigour, dedication and absorption, in accordance with the Utrecht Work Engagement scale designed by Schaufeli and Bakker (2004a). Items were formulated as statements such as: ‘I can continue working for very long periods at a time’, followed by a seven-point Likert-type scale with 1 representing never and 7 representing always/on a daily basis.

Procedure

For this article, variance-based structural equation modelling (Henseler, 2017) was used as an analytical tool; this type of modelling allows for explorative research and estimating the predicting power for structured equation models (Hair et al., 2017; Henseler et al., 2016). Among variance-based structural equation modelling systems, partial least squares structural equation modelling (PLS-SEM) path modelling is the most fully developed (Hair et al., 2011). PLS-SEM has been subject of various reviews, discussions and serious examinations (cf. Henseler et al., 2016), which has led to substantial contributions and increased robustness of PLS-SEM algorithms, including bootstrap-based tests of the overall model fit and consistent PLS-SEM to estimate factor models (for an overview, see Henseler, 2017). As the nature of our research is exploratory, there is a specific interest in the predicting power of the constructs used. Therefore, SMART-PLS version 3.2.7 (Ringle et al., 2015) was used to analyse the model.

First, the validity and reliability of the model were examined. Validity entails the extent to which a construct accurately measures what it is intended to measure. This is checked through determining construct validity and convergent validity. Reliability considers the consistency of results that the model produces (Sekaran and Bougie, 2011). Construct validity indicates how well the results obtained from the use of the measure fit the theories around which the test is constructed. This is assessed by determining convergent validity, which is established when there is a high correlation between the scores obtained by two different instruments measuring the same concept, and discriminant validity, which occurs when two variables are predicted and empirically proved to have no correlation (Sekaran and Bougie, 2011).

Second, the path weighting scheme was used for the partial least square algorithm. The maximum number of iterations was set at 300, and 10⁻⁵ was used as stop criterion. A uniform value of 1 was used as the initial value for each of the outer weights (Henseler, 2010). Considering the rule of thumb provided by Barclay et al. (1995) suggesting the use of 10 times the maximum number of paths aiming at any construct in the outer and inner models, the sample size was considered acceptable. The items were based on a five-point Likert-type scale (except for the shared leadership items, which were based on a seven-point Likert-type scale) and could be interpreted as continuous variables, thus following the fundamental OLS principles.

Results

Model characteristics

For the outer model evaluation, reliability was examined first. All scales appeared to be larger than 0.7 and therefore reliable (Nunnally, 1978) without removing an item, as demonstrated in Table 2. Second, convergent validity was checked using Fornell and Larcker’s (1981) criterion of an average variance extracted (AVE) for each construct above the 0.5 benchmark. The model demonstrated sufficient convergent validity, the AVE for all constructs being above 0.5 (see Table 2).

Table 2.

Reliability and convergent validity scores.

Construct	Theoretical range	Actual range	Mean	SD	Reliability	AVE
Quality of the open innovation process	1–7	1.00–7.00	5.05	1.01	0.91	0.65
Transactional leadership behaviour	1–7	1.00–7.00	4.66	1.24	0.94	0.72
Transformational leadership behaviour	1–7	1.00–7.00	4.80	1.02	0.94	0.51
Employee engagement	1–7	1.00–7.00	4.91	0.83	0.93	0.50

Note: SD: standard deviation; AVE: average variance extracted.

Finally, discriminant validity was checked by comparing the AVEs of the constructs with the inter-construct correlations determining whether each latent variable shared greater variance with its own measurement variables or with other constructs (Chin, 1998; Fornell and Larcker, 1981). The square root of the AVE was compared for each construct with the correlations with all other constructs in the model. A correlation between constructs exceeding the square roots of their AVEs indicates that they may not be sufficiently discriminable (Table 3). For each construct, it was found that the absolute correlations did not exceed the square roots of the AVEs. Hence, all constructs showed sufficient reliability and validity.

Table 3.

Correlation table.

Construct	Engagement	Open innovation	Transactional leadership	Transformational leadership
Engagement	0.71
Quality of the open innovation process	0.52**	0.80
Transactional leadership	0.46**	0.51**	0.85
Transformational leadership	0.53**	0.65**	0,67**	0.72

Note: Values in italics, square root of AVE. AVE: average variance extracted.

**Significant at the 0.01 level, two-tailed.

Common-method variance

The current article includes a test for common-method variance (CMV) to evidence that there is no systematic bias that might have influenced the collected data (Podsakoff et al., 2003). A two-step approach was adopted. First, following Podsakoff and Organ (1986), Harman’s (1976) one-factor test was used. In line with this approach, all principal constructs were entered into one principal component factor analysis. Using SPSS software (SPSS version 22 for Windows), the extraction method of principal component of one fixed factor with none rotation method was applied. Results showed that one fixed factor explained less than 50% of the variance (34.07%). This provided a first indication of no CMV. Second, Bagozzi’s method (Bagozzi et al., 1991) was applied, which stresses that CMV occurs when the highest correlation between constructs is more than 0.9. As shown in Table 2, the highest correlation between constructs is 0.67 (correlation between transactional and transformational leadership). Therefore, it appears that there is no CMV in the collected data.

Model estimations

Regarding the inner model evaluation and estimates, the path coefficients were analysed using bootstrap t-statistics for their significance (Anderson and Gerbing, 1988). For this PLS consistent bootstrapping, 5000 subsamples were used, with a bias-corrected bootstrap, testing for a two-tailed significance of 95%. The model showed sufficient model fit: the standardized root mean square residual was 0.071, which is in line with Hu and Bentler’s (1998) criterion of a value lower than 0.080. To test the hypotheses formulated, a three-step approach was utilized. First, in relation to predicting power, the R ² and Q ² were calculated for engagement and open innovation. Q ² measures the ability of the model to reconstruct observed values and evaluates the predictive validity of the structural model. Second, the direct effects for the differentiated paths in the model were calculated (see Table 4). Finally, predictive power was tested using Cohen’s (1988) f ² effect size to indicate whether each construct had a weak, average or strong effect on ‘the open innovation process’ (see Table 4).

Table 4.

Variances and Stone–Geisser’s Q ² outcomes.

Construct	R ²	Adjusted R ²	Q ²
Engagement	0.305	0.297	0.14
Quality of the open innovation process	0.47	0.46	0.27

As a first step, this research used the variance and adjusted variance of work engagement (R ² = 0.305, R ² adjusted = 0.297) and open innovation (R ² = 0.47, R ² adjusted = 0.46) with the help of the PLS consistent algorithm. Second, the blindfolding procedure was applied (Hair et al., 2017) to calculate Stone–Geisser’s Q ² value (Stone, 1974; Geisser, 1974), which is a criterion of predictive relevance. Strong Q ² values were found for work engagement (Q² = 0.14) and for open innovation (Q² = 0.27) (see Hair et al., 2017, for the thresholds for low, moderate and strong Q ² values). Hence, these values indicate a strong predicting power for the two aforementioned constructs and the model in general. An overview of the R ², R ² adjusted and Q ² values is provided in Table 4.

The analysis demonstrated that hypothesis 1 was not supported by the data, for the relationship between transactional leadership and the open innovation process was not significant (γ = 0.09, p = 0.35). In support of hypothesis 2, however, transformational leadership demonstrated to have a strong significant relationship with the open innovation process (γ = 0.47, p = 0.000, f ² = 0.20). Furthermore, work engagement was positively related to the open innovation process, in a moderate way (γ = 0.23, p = 0.002, f ² = 0.07), which supports hypothesis 3. As no significant relationship was found between transactional leadership and work engagement (γ = 0.19, p = 0.06), hypothesis 4 was not supported. Finally, in line with hypothesis 5, transformational leadership was found to have a strong positive relationship with work engagement (γ = 0.41, p = 0.000, f ² = 0.13). Table 5 presents the path analyses and the f ² scores.

Table 5.

Overview path-analysis and f ² scores.

	γ-Coefficient	γ-Coefficient bootstrap	Standard deviation	p-Values	F ²
Engagement
Quality of the open innovation process	0.23	0.23	0.07	0.002	0.07
Transactional leadership
Engagement	0.19	0.19	0.10	0.06
Quality of the open innovation process	0.09	0.08	0.10	0.35
Transformational leadership
Engagement	0.41	0.42	0.09	0.00	0.13
Quality of the open innovation process	0.47	0.48	0.09	0.00	0.20

Discussion

This study aimed to contribute to the scholarly debates on leadership and open innovation, leadership and work engagement by examining how both transactional and transformational leadership relate to the quality of the open innovation process as perceived by employees, and whether these relationships are (partly) mediated by work engagement. Below, the results of the study will be summarized and discussed.

The role of transactional and transformational leadership in the quality of the open innovation process as perceived by employees

First, no significant positive relationship was found between how employees perceive their leader to be transactional (focusing on rewards) and the quality of the open innovation process. This finding was inconsistent with the literature, as specifically the importance of a reward system is mentioned as a predictor of the quality of the open innovation process (Chesbrough, 2003a). Furthermore, according to Brown et al. (1996), the increased stability that stems from transactional leadership behaviour was expected to counter the reluctance that might arise when adopting an approach which makes contributions of employees more ambiguous (Almirall and Casadesus-Masanell, 2010). Possibly, the non-significant direct relationship between employees’ perceptions of transactional leadership and the perceived quality of the open innovation process can be explained by the fact that contingent reward is dependent on a leader’s or organization’s access to resources (cf. Judge and Piccolo, 2004). Moreover, a longitudinal research design might have been able to reveal a significant relationship if access to resources had changed over time (Judge and Piccolo, 2004).

Second, in line with expectations, however, perceived transformational leadership behaviour was found to have a significant positive relationship with employees’ perceptions of the quality of the open innovation process, which corroborates reports in the literature that this type of leadership stimulates the open innovation process (De Jong et al., 2018; Gumusluoglu and Ilsev, 2009; Hansen and Von Oetinger, 2001; Latham, 2014). A possible explanation for the significant direct relationship between employees’ perception of transformational leadership and the perceived quality of the open innovation process may be provided by autonomy, which has been shown to support open innovation (Burchart et al., 2017) and which is facilitated by transformational leadership behaviour (Bass, 1999). This finding not only adds to the scholarly debate on how open innovation should be led and managed (Vanhaverbeke et al., 2014) but also complements recent studies that advocate the role of specific leadership behaviour in the open innovation process (Ahn et al., 2017; Rangus and Černe, 2017).

The mediating role of work engagement in the relationship between leadership and the quality of the open innovation process as perceived by employees

First, no evidence was found for the mediating role of work engagement in the relationship between transactional leadership and employees’ perceptions of the open innovation process. This finding is not in accordance with the work reported by Breevaart et al. (2014) and Nedon (2015) who advocated that contingent rewarding would be positively related to employees’ perceptions of the open innovation process through higher levels of work engagement. However, this finding does coincide with the statement made by Bass and Avolio (1994) that the effectiveness of contingent reward systems depends on the access to resources that is available to the leaders’ organizations (Judge and Piccolo, 2004), making this mechanism more susceptible to situational circumstances.

Second, in line with expectations, a significant positive relationship was found between work engagement and the quality of the open innovation process as perceived by employees. This corresponds with reports in the literature which state that more engaged employees are more creative in finding solutions to problems in their work (Bakker et al., 2006), that these employees are more resourceful (Schaufeli and Bakker, 2004b; Shirom, 2003) and that they possess higher levels of self-efficacy (Schaufeli et al., 2001). Furthermore, reports show that work engagement positively influences the employees’ perceptions of the open innovation process. All these personal resources may also stimulate the open innovation process in which employees participate (Fleming and Waguespack, 2007; Mumford and Licuanan, 2004), and they provide insight into how employees draw upon their resources to support them in the role in the open innovation process (West et al., 2014).

Third, and related to the above, it was shown that work engagement (partly) mediated the relationship between perceived transformational leadership behaviour and open innovation. This finding supports the literature which stresses the positive effect of transformational leadership on work engagement (Tims et al., 2011) and the mediating role of engagement (Salanova et al., 2011), and it shows that employees who are more creative, confident (Bandura, 1997) and engaged (Bakker et al., 2006) are more engaged in open innovation. This finding adds to the discussion on how open innovation must be steered and organized (Vanhaverbeke et al., 2014) by showing the positive effect of transformational leadership and work engagement on the quality of the open innovation process as perceived by the participants in the process.

Limitations and suggestions for further research

Scholarly research into the quality of the open innovation process and the factors that influence this process remains ongoing. The present study indicated that direct and indirect relationships exist between specific leadership behaviours (transformational leadership) and the open innovation process. Moreover, it demonstrated the mediating role of work engagement in this relationship. Nevertheless, this research has been subject to various limitations which indicate interesting areas for future research.

First, the direct and indirect relationships between transactional leadership and open innovation were shown to be positive, but non-significant. Judge and Piccolo (2004) indicated that contingent rewarding might show differential results when investigated within an alternative research design, rather than in a cross-sectional design as used in this study. Future studies into the relationship between transactional leadership and open innovation may employ a longitudinal design that can provide greater insight into the causes and effects of relationships. Preferably, such a longitudinal study should focus on subdimensions of the transactional leadership concept, as this will help to determine the causality of the respective relationships between the different subdimensions of the constructs to a greater extent.

Second, and more generally, more in-depth research may be needed to focus on the relationships between perceived transactional leadership behaviour, work engagement and the three phases in the open innovation process, as previous studies have shown contradicting results (cf. Breevaart et al., 2014; Chesbrough et al., 2003a).

Third, more research is required into the relationship between differential leadership styles and self-efficacy, and the subsequent effect on the quality of the open innovation process, as previous literature has indicated that self-efficacy might increase employees’ abilities not only to create their own resources (Schaufeli and Bakker, 2004b; Shirom, 2003) but also their capacity for developing creative solutions in their work (Bakker et al., 2006; Gong et al., 2009).

Fourth, as work engagement and perceptions of employees are influential to the quality and outcomes of open innovation projects (Brunswicker and Chesbrough, 2018; Nedon, 2015), another interesting topic that requires more research would be the relationship between employees’ perceptions of the open innovation process and the extent to which these perceptions influence the actual outcomes of this process.

Managerial implications

This research indicated that the open innovation process is directly and indirectly supported by perceived transformational leadership behaviour. Therefore, a twofold recommendation is proposed implying that managers should focus both on finding ways to create transformational leadership behaviour and on fostering work engagement. First, organizations should take into account how perceived transformational leadership behaviour can stimulate creativity and innovative thinking (Gong et al., 2009; Gumusluogu and Ilsev, 2009) and hence stimulate the quality of the open innovation process (Chesbrough, 2003a; Mumford and Licuanan, 2004). Examples of specific behavioural attributes for leaders to focus on include shaping and articulating a clear and compelling vision which demonstrates the importance of the teams’ creative efforts for their organizations. This is especially important in an open innovation context, as this behaviour has the potential to unify teams (To et al., 2015). In guiding employees through the open innovation process in line with their vision, leaders should provide direct support and intellectual stimulation to employees by continuously challenging them to question the status quo. Aside from challenging employees to become more creative, this can decrease the fear that might arise due to the uncertainty and ambiguity associated with engaging in creative processes (Gong et al., 2009).

Secondly, while transformational leadership improves the creative self-efficacy of employees (Gong et al., 2009), this study showed that a leader’s transformational leadership style could support open innovation even further as it can enhance employees’ work engagement. Leaders can accomplish this, for example, by aiding their employees in their career management and by linking their career management goals to their active participation in the open innovation process. More specifically, leaders can introduce regular feedback sessions and periodical reviews with their employees to ensure that their participation in the open innovation process supports their personal and professional development goals (Schaufeli and Salanova, 2010). This alignment between the employees’ goals and their engagement in the open innovation process can be strengthened further by providing the employees with training that is focused on their personal and professional development, such as the acquisition of job-specific and more generic skills and competencies such as networking and collaborating across organizational boundaries (Swart and Kinnie, 2014). This way, participation in the open innovation process can help the employees to become both better at their jobs and prepare them for their next roles, be it inside or outside the organization (Schaufeli and Salanova, 2010; Swart and Kinnie, 2014).

Footnotes

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding

The authors received no financial support for the research, authorship and/or publication of this article.

References

Ahn

Minshall

Mortara

(2017) Understanding the human side of openness: the fit between open innovation modes and CEO characteristics. R&D Management 47(5): 727–740.

Almirall

Casadesus-Masanell

(2010) Open versus closed innovation: a model of discovery and divergence. Academy of Management Review 35(1): 27–47.

Anderson

Gerbing

(1988) Structural equation modeling in practice: a review and recommended two-step approach. Psychological Bulletin 103(3): 411–423.

Avolio

Zhu

Koh

, et al. (2004) Transformational leadership and organizational commitment: mediating role of psychological empowerment and moderating role of structural distance. Journal Organizational Behavior 25(8): 951–968.

Bagozzi

Phillips

(1991) Assessing construct validity in organizational research. Administrative Science Quarterly 36(3): 421–458.

Bahemia

Squire

(2010) A contingent perspective of open innovation in new product development projects. International Journal of Innovation Management 14(4): 603–627.

Bakker

Demerouti

Verbeke

(2004) Using the job demands: resources model to predict burnout and performance. Human Resource Management 43(1): 83–104.

Bakker

Gierveld

Van Rijswijk

(2006) Succesfactoren bij vrouwelijke schoolleiders in het primair onderwijs: Een onderzoek naar burnout bevlogenheid en prestaties [Success factors among female school principals in primary teaching: A study on burnout work engagement and performance]. Diemen, the Netherlands: Right Management Consultants.

Bandura

(1997) Self-Efficacy: The Exercise of Control. New York: W H Freeman/Times Books/ Henry Holt and Co.

10.

Barclay

Higgins

Thompson

(1995) The partial least squares approach to causal modeling: personal computer adoption and use as illustration. Technology Studies 2(2): 285–309.

11.

Barrick

Thurgood

Smith

, et al. (2015) Collective organizational engagement: linking motivational antecedents strategic implementation and firm performance. Academy of Management Journal 58(1): 111–135.

12.

Bass

(1998) Transformational Leadership: Industry Military and Educational Impact. Mahwah: Lawrence Erlbaum Associates.

13.

Bass

(1999) Two decades of research and development in transformational leadership. European Journal of Work and Organizational Psychology 8(1): 9–32.

14.

Bass

Avolio

(1994) Improving Organizational Effectiveness through Transformational Leadership. Thousand Oaks: Sage.

15.

Bass

Avolio

(1995) MLQ Multifactor Leadership Questionnaire, Leader Form, Rater Form, and Scoring. Palo Alto, CA: Mind Garden.

16.

Baum

JAC

Calabrese

Silverman

(2000) Don’t go it alone: alliance network composition and startups performance in Canadian biotechnology. Strategic Management Journal 21(3): 267–294.

17.

Bogers

Foss

Lyngsie

(2018) The “human side” of open innovation: the role of employee diversity in firm-level openness. Research Policy 47(1): 218–231.

18.

Bogers

Zobel

Afuah

, et al. (2017) The open innovation research landscape: established perspectives and emerging themes across different levels of analysis. Industry and Innovation 24(1): 8–40.

19.

Breevaart

Bakker

Hetland

, et al. (2014) Daily transactional and transformational leadership and daily employee engagement. Journal of Occupational Organizational Psychology 87(1):138–157.

20.

Brown

McLean

Straub

(1996) Partnering roles of the IS executive. Information Systems Management 13(2): 14–18.

21.

Brunswicker

Chesbrough

(2018) The adoption of open innovation in large firms. Research-Technology Management 61(1): 35–45.

22.

Burcharth

ALDA

Knudsen

Søndergaard

(2014) Neither invented nor shared here: the impact and management of attitudes for the adoption of open innovation practices. Technovation 34(3): 149–161.

23.

Burns

(1978) Leadership. New York: Harper and Row.

24.

Chesbrough

(2003a) Open Innovation the New Imperative for Creating and Profiting from Technology. Boston: Harvard Business School Press.

25.

Chesbrough

(2003b) The era of open innovation. MIT Sloan Management Review 44(3): 35–41.

26.

Chesbrough

(2006) Open Business Models: How to Thrive in the New Innovation Landscape. Boston: Harvard Business School Press.

27.

Chesbrough

Bogers

(2014) Explicating open innovation: Clarifying an emerging paradigm for understanding innovation. In Chesbrough

Vanhaverbeke

West

(eds) New Frontiers in Open Innovation. Oxford, UK: Oxford University Press, pp. 3–28.

28.

Chesbrough

Vanhaverbeke

West

(2014) New Frontiers in Open Innovation. Oxford: Oxford University Press.

29.

Chin

(1998) The partial least squares approach to structural equation modeling. In: Marcoulides

(ed) Modern methods for business research. Mahwah: Lawrence Erlbaum Associates, pp. 295–336.

30.

Cohen

(1988) Statistical Power Analysis for the Behavioral Sciences, 2nd ed. Hillsdale: Lawrence Erlbaum Associates.

31.

De Jong

Blomme

Lub

(2018) Unlocking the potential of outsourcing the key: authentic leadership as accelerator of open innovation. International Journal of Business and Globalisation 20(4): 557–577.

32.

Den Hartog

Belschak

(2012) When does transformational leadership enhance employee proactive behavior? The role of autonomy and role breadth self-efficacy. Journal of Applied Psychology 97(1): 194–202.

33.

Fleming

Waguespack

(2007) Brokerage boundary spanning and leadership in open innovation communities. Organization Science 18(2): 165–180.

34.

Fornell

Larcker

(1981) Structural equation models with unobservable variables and measurement error: algebra and statistics. Journal of Marketing Research 18(3): 382–388.

35.

Frambach

Schillewaert

(2002) Organizational innovation adoption: a multi-level framework of determinants and opportunities for future research. Journal of Business Research 55(2): 163–176.

36.

Gassmann

Enkel

Chesbrough

(2010) The future of open innovation. R&D Management 40(1): 213–221.

37.

Geisser

(1974) A predictive approach to the random effects model. Biometrika 61(1): 101–107.

38.

Giannopoulou

Yström

Ollila

, et al. (2010) Implications of openness: a study into (all) the growing literature on Open innovation. Journal of Technology Management and Innovation 5(3): 162–180.

39.

Gong

Huang

Farh

(2009) Employee learning orientation transformational leadership and employee creativity: the mediating role of employee creative self-efficacy. Academy of Management Journal 52(4): 765–778.

40.

Gumusluoglu

Ilsev

(2009) Transformational leadership creativity and organizational innovation. Journal of Business Research 62(4): 461–473.

41.

Hair

Hult

Ringle

, et al. (2017) A Primer on Partial Least Squares Structural Equation Modeling (PLS-SEM), 2nd ed. Thousand Oaks: Sage.

42.

Hair

Ringle

Sarstedt

(2011) PLS-SEM: indeed a silver bullet. Journal of Marketing Theory and Practice 19(2): 139–151.

43.

Hansen

Von Oetinger

(2001) Introducing T-shaped managers: knowledge managements next generation. Harvard Business Review 79(3): 106–116.

44.

Harman

(1976) Modern Factor Analysis, 3rd ed. Chicago: University of Chicago Press.

45.

Hater

Bass

(1988) Superiors evaluations and subordinates perceptions of transformational and transactional leadership. Journal of Applied Psychology 73(4): 695–702.

46.

Henseler

(2010) On the convergence of the partial least squares path modeling algorithm. Computational Statistics 25(1): 107–120.

47.

Henseler

(2017) Bridging design and behavioral research with variance-based structural equation modeling. Journal of Advertising 46(1): 178–192.

48.

Henseler

Hubona

Ray

(2016) Using PLS path modeling in new technology research: updated guidelines. Industrial Management and Data Systems 116(1): 2–20.

49.

Hoch

(2013) Shared leadership and innovation: the role of vertical leadership and employee integrity. Journal of Business and Psychology 28(2): 159–174.

50.

Bentler

(1998) Fit indices in covariance structure modeling: sensitivity to underparameterized model misspecification. Psychological methods 3(4): 424–553.

51.

Huizingh

EKRE

(2011) Open innovation: state of the art and future perspectives. Technovation 31(1): 2–9.

52.

Joshi

Lazarova

Liao

(2009) Getting everyone on board: the role of inspirational leadership in geographically dispersed teams. Organization Science 20(1): 240–252.

53.

Judge

Piccolo

(2004) Transformational and transactional leadership: a meta-analytic test of their relative validity. Journal of Applied Psychology 89(5): 755–768.

54.

Kahn

(1990) Psychological conditions of personal engagement and disengagement at work. Academy of Management Journal 33(4): 692–724.

55.

Kuhnert

Lewis

(1987) Transactional and transformational leadership: a constructive/developmental analysis. Academy of Management Review 12(4): 648–657.

56.

Latham

(2014) Leadership for quality and innovation: challenges theories and a framework for future research. Quality Management Journal 21(1): 11–15.

57.

Lichtenthaler

(2011) Open innovation: past research current debates and future directions. Academy of Management Perspectives 25(1): 75–93.

58.

MacLeod

Clarke

(2009) Engaging for Success: Enhancing Performance through Employee Engagement. London: Department for Business Innovation and Skills (BIS).

59.

Medlin

Green

(2014) Impact of management basics on employee engagement. Academy of Strategic Management Journal 13(2): 21–35.

60.

Mumford

Licuanan

(2004) Leading for innovation: conclusions issues and directions. The Leadership Quarterly 15(1): 163–171.

61.

Nedon

(2015) Open Innovation in R&D departments: An Analysis of Employees Intention to Exchange Knowledge in OI-Projects. Wiesbaden: Gabler Verlag.

62.

Nonaka

(1994) A dynamic theory of organizational knowledge creation. Organization Science 5(1): 14–37.

63.

Nunnally

(1978) Psychometric Theory, 2nd ed. New York: McGraw-Hill.

64.

Ozaralli

(2003) Effects of transformational leadership on empowerment and team effectiveness. Leadership and Organization Development Journal 24(6): 335–344.

65.

Pearce

Sims

(2002) Vertical versus shared leadership as predictors of the effectiveness of change management teams: an examination of aversive directive transactional transformational and empowering leader behaviors Group Dynamics: Theory Research and Practice 6(2): 172–197.

66.

Podsakoff

Organ

(1986) Self-reports in organizational research: problems and prospects. Journal of Management 12(4): 69–82.

67.

Podsakoff

Bommer

Podsakoff

, et al. (2006) Relationships between leader reward and punishment behavior and subordinate attitudes perceptions and behaviors: a meta-analytic review of existing and new research. Organizational Behavior and Human Decision Processes 99(2): 113–142.

68.

Podsakoff

MacKenzie

Lee

, et al. (2003) Common method biases in behavioral research: a critical review of the literature and recommended remedies. Journal of Applied Psychology 88(5): 879–903.

69.

Rangus

Černe

(2017) The impact of leadership influence tactics and employee openness toward others on innovation performance. RD Management 49(2): 168–179.

70.

Ringle

Wende

Becker

(2015) SmartPLS3. Boenningstedt: SmartPLS GmbH. Available at: http://www.smartpls.com (accessed 6 March 2019).

71.

Salanova

Lorente

Chambel

, et al. (2011) Linking transformational leadership to nurses extra-role performance: the mediating role of self-efficacy and work engagement. Journal of Advanced Nursing 67(10): 2256–2266.

72.

Salter

Ter Wal

ALJ

Criscuolo

, et al. (2015) Open for ideation: individual level openness and idea generation in R&D. Journal of Product Innovation Management 32(4): 488–504.

73.

Schaufeli

Bakker

(2004a) Bevlogenheid: Een begrip gemeten. Gedrag en Organisatie 17(2): 89–111.

74.

Schaufeli

Bakker

(2004b) Job demands job resources and their relationship with burnout and engagement: a multi-sample study. Journal of Organizational Behavior 25(3): 293–315.

75.

Schaufeli

Salanova

(2007) Work engagement: an emerging psychological concept and its implications for organizations. In: Gilliland

Steiner

Skarlicki

(eds) Managing Social and Ethical Issues in Organizations. Greenwich: Information Age, pp. 135–177.

76.

Schaufeli

Salanova

(2010) How to improve work engagement? In: Albrecht

(ed) Handbook of Employee Engagement: Perspectives Issues Research and Practice: Cheltenham: Edward Elgar, pp. 399–415.

77.

Schaufeli

Taris

Le Blanc

, et al. (2001, September) Maakt arbeid gezond? Op zoek naar de bevlogen werknemer [Scientific article]. Available at: edshttp://www.wilmarschaufeli.nl/publications/Schaufeli/165n.pdf. (accessed 6 March 2019).

78.

Sekaran

Bougie

(2011) Research Methods for Business: A Skill-building Approach, 5th ed. West Sussex: John Wiley & Sons.

79.

Shirom

(2003) Feeling vigorous at work? The construct of vigor and the study of positive affect in organizations. In: Ganster

Perrewe

(eds) Research in Organizational Stress and Well-being. Greenwich: JAI Press, pp. 135–165.

80.

Simonin

(1997) The importance of collaborative know-how: an empirical test of the learning organization. Academy of Management Journal 40(5): 1150–1174.

81.

Spreitzer

Lam

Fritz

(2010) Engagement and human thriving: complementary perspectives on energy and connections to work. In: Bakker

Leiter

(eds) Work Engagement: A Handbook of Essential Theory and Research. New York: Psychology Press, pp. 132–146.

82.

Stone

(1974) Cross-validatory choice and assessment of statistical predictions. Journal of the Royal Statistical Society Series B 36(2): 111–133.

83.

Swart

Kinnie

(2014) Reconsidering boundaries: human resource management in a networked world. Human Resource Management 53(2): 291–310.

84.

Tims

Bakker

Xanthopoulou

(2011) Do transformational leaders enhance their followers daily work engagement? Leadership Quarterly 22(1): 121–131.

85.

Tse

HHM

Ashkanasy

(2015) A multilevel model of transformational leadership affect and creative process behavior in work teams. The Leadership Quarterly 26(4): 543–556.

86.

Vanhaverbeke

West

Chesbrough

(2014) Surfing the new wave of open innovation research. In: Chesbrough

Vanhaverbeke

West

(eds) New Frontiers in Open Innovation. Oxford: Oxford University Press, pp. 281–294.

87.

Walumbwa

Orwa

(2008) Contingent reward transactional leadership work attitudes and organizational citizenship behavior: the role of procedural justice climate perceptions and strength. Leadership Quarterly 19(3): 251–265.

88.

West

Gallagher

(2006) Challenges of open innovation: the paradox of firm investment in open-source software. R&D Management 36(3): 319–331.

89.

West

Salter

Vanhaverbeke

, et al. (2014) Open innovation: the next decade. Research Policy 43(5): 805–811.

90.

West

Vanhaverbeke

Chesbrough

(2006) Open innovation: a research agenda. In: Chesbrough

Vanhaverbeke

West

(eds) Open Innovation: Researching a New Paradigm. Oxford: Oxford University Press. pp. 285–307.

91.

Zhu

Avolio

Walumbwa

(2009) Moderating role of follower characteristics with transformational leadership and follower work engagement. Group and Organization Management 34(5): 590–619.