From Table 9.7, it can be drawn that shared leadership is a more relevant predictor (i.e. of the
predictors considered here) for Team market proactiveness (explaining 23%), Team market
responsiveness (explaining 11%) and Team efficiency (explaining 4%). Vertical leadership is a more
relevant predictor for Team innovation (explaining 4%).
9.6 DISCUSSION
In this study, shared leadership and vertical leadership were largely unrelated, despite the claim that
vertical team leaders may promote (Bennis & Nanus, 1985; Diaz-Saenz, 2011) or limit shared
leadership. Comparing shared leadership with vertical leadership showed that shared leadership was a
more important predictor for team effectiveness than vertical leadership. In particular, shared
leadership was a significant predictor for the Environment-oriented Team effectiveness measures,
Market proactiveness and Market responsiveness. These findings are in line with the argumentation of
Pearce and Conger (2003a) who argue that organizations increasingly use teams as a predominant
strategy when faced with environments characterized by complexity and ambiguity. Hence teams
where externally oriented leadership behaviors are shared are more effective in terms of proactive and
responsive market orientation.
The internally-oriented team effectiveness measures, Team efficiency and Team innovation, turned
out to be unrelated to leadership (shared and vertical). At least the regression did not show any
significant values for these two team effectiveness measures. Even though a very dated study has
shown that if the dependent variable is team efficiency, the summation of individual proficiency
allows relative poor prediction (Wiest et al., 1961), also team efficiency cannot be related by means of
one-to-one relationship with leadership performed by the team leader. One may argue that team
efficiency may be more prone for distributed leadership, i.e. specific division of functional roles
DFURVV WHDP PHPEHUV ³7he collective effect of individual actions can only be understood by
examining the structure ± or combination ± of roles within a team (Schneider et al., 2000) ́(Stewart et
al., 2005, p.345). The notion of a collective role structure has been pursued by researchers examining
the prevalence and dispersion of roles within teams (Belbin, 1993; Partington & Harris, 1999; Senior,
1997). Bales and Slater (1955) hypothesized that in group interaction, a process of role differentiation
takes place along task and people-oriented diPHQVLRQV7KH\IRXQGWKDWDWWKHHQGRIWKHJURXS¶VILUVW
meeting, there is a 50% chance that the task-oriented leader will be the most liked. This reduces to
25% at the end of the second meeting, about 16% by the third, and even less by the fourth meeting.