Task performance:

Question: Do groups outperform individuals?

Answer: Depends on the task type and how the two are compared.

Question: What factors influence the quantity and quality of group performance?

Some Answers: Task structure (Steiner), group goals, process losses (or gains), membership composition

Task structure: Steiner's typology

Divisible or Unitary?

Finding examples in an essay, typing the essay

Packing the rafts for a river trip, lifting boats.

Maximizing or Optimizing?

Get down the river in record time; choose an ideal path through the rapids.

How are Inputs Related?

Determines relation of group to member performance

Determines potential productivity (groups frequently don't achieve potential because of process losses)

How are Inputs Related?


Performance exceeds best member

"The more, the merrier"


Group performance should be better than most members

Why: Because averaging reduces errors


Performance should match the best member

NOTE: Group needs to recognize best member


Performance determined by worst member

"One bad apple" "Weak link"

NOTE: Matching can help when task divisible


Group determines how inputs are combined

Performance depends on how they're combined