9.4 METHOD
9.4.1 SAMPLE
The sample for this study has been described in chapter eight, but requires some elaboration for this
particular study. The initial sample of 158 focal managers was separated in a sample of formal team
leaders and a sample of team members (excluding the formal team leader). The distinction between
formal team leader and team member was reported upon administration for the survey. 6 of the 35
teams were self-managing teams, without a formal team leader. These teams were excluded from the
sample (for this last study). Hence the sample for this study consisted of 139 focal managers from 29
teams, where the 139 focal managers were rated by 443 colleagues (superiors, peers and
subordinates).
The sample of 139 focal managers was separated in two parts, resulting in 29 formal team leaders and
110 team members. In other words, the sample consisted out of 29 teams, consisting out of formal
team leader and out of a set of team members (with an average of 3.79 team member per team).
The formal team leaders were considered in order to measure vertical leadership and the team
members to measure shared leadership per team. The typical profile of the formal team leader was
male (76%), 48.5 years old (average age of subsample), Dutch (79% ZLWKD0DVWHU¶VGHJUHH %),
functioning in current position between 1 to 3 years (48%). The typical profile of a team member was
male (57%), 41 years old (average age of this subsample), Dutch (68% ZLWK D 0DVWHU¶V GHJUHH
(56%).
MEASURES
Vertical leadership
Vertical leadership was measured on the basis of the strategic leadership dimensions described in
earlier chapters. These scores were calculated by averaging the scores of different raters, resulting in
individual scores for the formal team leaders on all four strategic leadership. Hence, there were 29
vertical leadership scores for four strategic leadership dimensions.
Shared leadership
Shared leadership was measured by means of the amplitude of strategic leadership within a team. First
of all the individual scores of the team members were calculated in a similar way as has been done for
the formal team leaders. These scores were based on the scores given by the different raters per
individual. Next, the individual scores of the team members were averaged across the teams, resulting