Abstract: There are 2 approaches in the area of team diversity research. The first approach is to categorize types of diversity and then subdivide it. Scholars subdivided the diversity into race, age, gender, character, functional background, tenure, educational level, and so on, and then studied the effects of diversity on performance. The second approach is to study the intervening process, i.e., conflict, which enables to determine the mechanism of the effect of diversity on performance. However, previous studies have some limitations. First, there is no comparison study on the 2 approaches. Secondly, previous studies hardly separated knowledge difference from diversity. Thirdly, these studies distinguished only the types of diversity but not the level of diversity. Hence, our study separated knowledge difference from team diversity and explored 3 questions. First, what is the impact of knowledge difference on team performance? Second, what is the difference between influence of knowledge difference alone and knowledge difference along with knowledge conflict on team performance? Third, what is the impact of different levels of knowledge difference on team performance?
Method
This study applied the experimental method and adopted a 2*2 between-subjects design. The independent variables were knowledge difference (2 levels: high and low) and knowledge conflict (2 levels: existent and inexistent). The dependent variable was creativity marks of the team. The experimental task required each team to present an innovative project based on experimental materials. Three experts used a 9-point rule to assign marks to these projects based on the level of creativity. The marks assigned by the 3 experts were summed to obtain the total creativity marks of each team. A total of 162 students (40 teams) participated in this experiment. ANOVA was used to analyze the data.
Results
1. When the level of knowledge difference was low, knowledge conflict played a positive role in team creativity; in contrast, when the level of knowledge difference was high, knowledge conflict may facilitate or restrain creativity. Thus, knowledge conflict played a fluctuating role.
2. When knowledge conflict was inexistent, high level of knowledge difference played a positive role in team creativity; when knowledge conflict was existent, the impact of teams with high level of knowledge difference on team creativity was not significantly different from that of teams with low level of knowledge difference.
Conclusion
In this study, knowledge difference was separated from team diversity and was associated with the variable of knowledge conflict in order to determine their effects on team creativity. There is an interaction between knowledge difference and knowledge conflict. Pure knowledge difference always positively affects creativity; however, when it is accompanied with knowledge conflict, mixed effects are observed. Knowledge difference along with knowledge conflict will not only strengthen creativity but also restrain it; this increases the risk of hampering team creativity. If the team needs to be considerably more creative, knowledge conflict should be encouraged in order to generate novel ideas. Although the cost of encouraging knowledge conflict involves the risk of considerably lower performance, it is worthy of implementing this strategy. If the team needs to be considerably more efficient, knowledge conflict should be restrained in order to achieve stable performance

Key words: knowledge difference, knowledge conflict, team creativity