The results of prior research on the impact of top management team (TMT) diversity on corporate performance have been varied and inconsistent. In this study, the operational definitions of TMT and diversity were checked in academic papers published between 2005 and 2020 on TMT diversity. The results confirmed three patterns for the operational definition of TMT: (a) extracted by title rank, (b) selected by CEO or equivalent top manager, and (c) executives announced in the company's public information/database. As for diversity, in addition to the studies that use conventional indices that express the various attributes of executives, it was confirmed that there exist many studies that consider diversity from the aspects of separation and disparity. Such “diversity” in the operational definition is considered the cause of the lack of consistency between TMT diversity and corporate performance.

This study examines the definition of shared leadership and how to measure it. Research so far defines shared leadership as possessing some basic common characteristics. However, the aggregation approach and the social network approach, which have different characteristics, coexist in terms of measurement methods. The former combines various existing leadership concepts and emphasizes the “leadership” part. The latter looks at how leadership is being shared; thus, the emphasis is on the “shared” part.

Previous research has demonstrated that different ways of interpreting the same stimulus can result in significantly different behaviors of and outcomes for the interpreters. This paper analyzes how employees interpret their workplaces from the perspective of the concept of “ambidexterity,” which is a part of the organizational learning theory. An analysis of the questionnaire survey data collected from 1,650 white-collar full-time employees in the Tokyo metropolitan region of Japan indicated that (a) there was a significant positive correlation between exploitation and exploration; (b) contrary to previous perceptions, no trade-off relationship was observed between the two, and (c) the “ambidexterity” group—which exhibited high levels of exploitation and exploration—tended to interpret the office as a place for “communication,” while the “neither” group—which exhibited a low levels of both these variables—tended to view the office as a place for “concentration.”

Rosenkopf and Nerkar (2001) examined the relationship between patents with a boundary-spanning exploration of organizations and technological domains and their impact on subsequent technological evolution, using patent data for optical disks as the technological domain. However, the results of their analysis will be affected by the size of the technological domain itself. Therefore, this study analyzes and compares (a) vector control technology for electric motors and (b) the larger technology domain that includes (a). The results indicate that in the case of (a), vector control technology, even when a boundary-spanning exploration is conducted, there is some outside impact, but no domain impact. By comparison, in the larger technology area (b), there was some domain impact, but less outside impact. In other words, the hypotheses were partially supported for vector control technology in electric motors; however, the wider the technological domain, the stronger the domain impact and the weaker the outside impact tended to be, and the impact is dependent on the granularity with which the technology field is defined.