We applaud Baumeister et al. for taking a fresh and comprehensive look at the costs and benefits of collaborative group work. As group researchers, we sympathize with their attempt to push a “one size fits all” approach as far as they can, trying to find the one key to group synergy under all conditions, instead of the so-far-dominating “it depends” answers to the question of how groups can achieve synergy. However, we are afraid that the concept of “differentiation of selves” is not the master key that Baumeister et al. want it to be.
In our view, a central problem of this concept is that “differentiation of selves” constitutes an umbrella term for somewhat similar seeming but actually very different theoretical constructs. For example, in the target article, sometimes “differentiation of selves” refers to actual differences between group members (e.g., with regard to roles, knowledge, expertise, or pre-discussion preferences). In other places, “differentiation of selves” refers to group members having metaknowledge about each other's differentiated identities within the group. And again in other places, “differentiation of selves” refers to group members perceiving themselves as autonomous, independent, responsible, or even indispensable individuals. Arguably, these are all very different theoretical constructs.
Imagine, for example, a group consisting of four members who have exactly the same personality characteristics, task-relevant skills, amount of knowledge and experience, and so forth. We suspect in such a case there will be no (or at least not much) “differentiation of selves” in terms of actual or perceived differences between members in this group. At the same time, however, group members may feel highly indispensable to the group's success. For example, let us assume that our team consists of mountain climbers who have to pass a difficult section of a route. Despite the lack of perceived or actual differences between members, each is likely to feel indispensable to the group's success because to reach the peak of the mountain, all members have to be successful in passing the difficult section. Hence, differentiation of selves in terms of actual or perceived differences between members and perceived indispensability are completely different constructs. As empirical group performance research shows, differentiating these constructs is not only necessary for the sake of theoretical precision, but also inevitable if one wants to accurately predict the effects of these constructs on group performance (e.g., Gockel et al. Reference Gockel, Kerr, Seok and Harris2008; Worchel et al. Reference Worchel, Rothberger, Day, Hart and Butemeyer1998).
However, even a more specific and less equivocal concept of differentiation of selves cannot serve as a universal key to high group performance; there is no way around one of the fundamental lessons to be learned from Ivan Steiner's (Reference Steiner1972) seminal analysis of group performance – namely, that the requirements of the tasks that groups perform will dictate what is successful and what is not. Therefore, what is successful for one type of task might be harmful for another. For example, let us assume that we specify “differentiation of selves” in terms of differences between members on attributes such as skills, personality, beliefs, and perspectives. In that case, differentiation of selves would be identical to what is called “deep-level diversity” in group performance research (e.g., Harrison et al. Reference Harrison, Price and Bell1998). As previous research has shown, such deep-level diversity can be beneficial for group performance in some tasks and detrimental in others (for a review, see Larson Reference Larson2010).
For example, in the case of divisible tasks, diversity in skills is likely to have a positive impact on performance, because each subtask can be performed by the group member who is best suited for it. Given optimal subtask assignments, skill diversity is hence likely to increase group performance. By contrast, skill diversity may have negative effects in the case of conjunctive tasks (i.e., indivisible tasks where the performance of the least capable member defines the group's level of performance). In such tasks, any group member's lack of a skill cannot be compensated by the skill of another group member. In the example of our climbing team, diversity in climbing skills is likely to have a negative impact on the team's success. Let us assume, for simplicity, that each group member is above average in one specific climbing-related skill and below average in another, and that all four group members have different strengths and weaknesses. Each member has to pass all sections of a route, so each member needs to possess all of the requisite climbing skills. By necessity, this means that the member with the least expertise in a skill sets the pace whenever that skill is required. As a consequence, the team is either slowed down or, in the worst case, unable to continue. The lesson is that the impact of skill diversity on group performance critically depends on the task the group performs.
Let us now suppose that our climbing team has to make a decision about which route to take, and the team members have different choice preferences. Previous research shows that diversity in choice preferences facilitates group decision quality (e.g., Schulz-Hardt et al. Reference Schulz-Hardt, Brodbeck, Mojzisch, Kerschreiter and Frey2006). At the same time, however, preference diversity may spark interpersonal conflict among members (Jehn Reference Jehn1994; Reference Jehn1995). As a consequence, such diversity is likely to hamper the implementation of decisions (e.g., White et al. Reference White, Dittrich and Lang1980). In other words, preference diversity can have both positive and negative effects on group performance, depending on whether groups have to make or implement a decision.
In conclusion, there is substantial empirical evidence that even the same type of differentiation between members in a group can be beneficial for some and harmful for other tasks. Hence, in spite of what the target article by Baumeister et al. suggests, and in spite of what we all might hope for, there is and can be no panacea for improving group performance.
We applaud Baumeister et al. for taking a fresh and comprehensive look at the costs and benefits of collaborative group work. As group researchers, we sympathize with their attempt to push a “one size fits all” approach as far as they can, trying to find the one key to group synergy under all conditions, instead of the so-far-dominating “it depends” answers to the question of how groups can achieve synergy. However, we are afraid that the concept of “differentiation of selves” is not the master key that Baumeister et al. want it to be.
In our view, a central problem of this concept is that “differentiation of selves” constitutes an umbrella term for somewhat similar seeming but actually very different theoretical constructs. For example, in the target article, sometimes “differentiation of selves” refers to actual differences between group members (e.g., with regard to roles, knowledge, expertise, or pre-discussion preferences). In other places, “differentiation of selves” refers to group members having metaknowledge about each other's differentiated identities within the group. And again in other places, “differentiation of selves” refers to group members perceiving themselves as autonomous, independent, responsible, or even indispensable individuals. Arguably, these are all very different theoretical constructs.
Imagine, for example, a group consisting of four members who have exactly the same personality characteristics, task-relevant skills, amount of knowledge and experience, and so forth. We suspect in such a case there will be no (or at least not much) “differentiation of selves” in terms of actual or perceived differences between members in this group. At the same time, however, group members may feel highly indispensable to the group's success. For example, let us assume that our team consists of mountain climbers who have to pass a difficult section of a route. Despite the lack of perceived or actual differences between members, each is likely to feel indispensable to the group's success because to reach the peak of the mountain, all members have to be successful in passing the difficult section. Hence, differentiation of selves in terms of actual or perceived differences between members and perceived indispensability are completely different constructs. As empirical group performance research shows, differentiating these constructs is not only necessary for the sake of theoretical precision, but also inevitable if one wants to accurately predict the effects of these constructs on group performance (e.g., Gockel et al. Reference Gockel, Kerr, Seok and Harris2008; Worchel et al. Reference Worchel, Rothberger, Day, Hart and Butemeyer1998).
However, even a more specific and less equivocal concept of differentiation of selves cannot serve as a universal key to high group performance; there is no way around one of the fundamental lessons to be learned from Ivan Steiner's (Reference Steiner1972) seminal analysis of group performance – namely, that the requirements of the tasks that groups perform will dictate what is successful and what is not. Therefore, what is successful for one type of task might be harmful for another. For example, let us assume that we specify “differentiation of selves” in terms of differences between members on attributes such as skills, personality, beliefs, and perspectives. In that case, differentiation of selves would be identical to what is called “deep-level diversity” in group performance research (e.g., Harrison et al. Reference Harrison, Price and Bell1998). As previous research has shown, such deep-level diversity can be beneficial for group performance in some tasks and detrimental in others (for a review, see Larson Reference Larson2010).
For example, in the case of divisible tasks, diversity in skills is likely to have a positive impact on performance, because each subtask can be performed by the group member who is best suited for it. Given optimal subtask assignments, skill diversity is hence likely to increase group performance. By contrast, skill diversity may have negative effects in the case of conjunctive tasks (i.e., indivisible tasks where the performance of the least capable member defines the group's level of performance). In such tasks, any group member's lack of a skill cannot be compensated by the skill of another group member. In the example of our climbing team, diversity in climbing skills is likely to have a negative impact on the team's success. Let us assume, for simplicity, that each group member is above average in one specific climbing-related skill and below average in another, and that all four group members have different strengths and weaknesses. Each member has to pass all sections of a route, so each member needs to possess all of the requisite climbing skills. By necessity, this means that the member with the least expertise in a skill sets the pace whenever that skill is required. As a consequence, the team is either slowed down or, in the worst case, unable to continue. The lesson is that the impact of skill diversity on group performance critically depends on the task the group performs.
Let us now suppose that our climbing team has to make a decision about which route to take, and the team members have different choice preferences. Previous research shows that diversity in choice preferences facilitates group decision quality (e.g., Schulz-Hardt et al. Reference Schulz-Hardt, Brodbeck, Mojzisch, Kerschreiter and Frey2006). At the same time, however, preference diversity may spark interpersonal conflict among members (Jehn Reference Jehn1994; Reference Jehn1995). As a consequence, such diversity is likely to hamper the implementation of decisions (e.g., White et al. Reference White, Dittrich and Lang1980). In other words, preference diversity can have both positive and negative effects on group performance, depending on whether groups have to make or implement a decision.
In conclusion, there is substantial empirical evidence that even the same type of differentiation between members in a group can be beneficial for some and harmful for other tasks. Hence, in spite of what the target article by Baumeister et al. suggests, and in spite of what we all might hope for, there is and can be no panacea for improving group performance.