Table 1.

Examples of different categories of group decisions.

	social sciences	natural sciences
groups with global overview
decision category: interactive/combined decisions
group decision	democratic/parliamentary votes	group activity synchronization
perspective	voting strategies	who decides and why?
references	Austen-Smith & Feddersen (2009), Hix et al. (2009) and many more	Conradt & Roper (2003, 2007, 2009), Rands et al. (2003) and Dostalkova & Spinka (2007)
group decision	common goods	movements in small groups
perspective	individual strategies	who decides and how?
references	Gächter & Herrmann (2009) and many more	Stewart & Harcourt (1994), Gompper (1996), Conradt & Roper (2005), Amé et al. (2006), Biro et al. (2006), Meunier et al. (2006), Fischhoff et al. (2007) and Sueur & Petit (2008)
group decision	international agreements	cooperative breeding
perspective	strategies	individual strategies
references	a large body of literature	Clutton-Brock (1998)
decision category: aggregate/consensus decisions
group decision	international agreements	group activity synchronization
perspective	patterns	segregation
references	a large body of literature	Conradt (1998), Ruckstuhl (1998, 1999), Conradt & Roper (2000), Ruckstuhl & Neuhaus (2000, 2002) and List (2004)
group decision	democratic/parliamentary votes	movements in small groups
perspective	systems	outcomes, speed, accuracy
references	a large body of literature	List (2004), Trillmich et al. (2004), Kerth et al. (2006), Gautrais et al. (2007), Sumpter et al. (2008) and Ward et al. (2008)
group decision	military orders or hierarchical decisions	cooperative hunting
perspective	any	patterns
references		Courchamp et al. (2002)
self-organizing systems
decision category: interactive/combined decisions
group decision	consumer choice	movements in large groups
perspective	how do consumers make choices?	mechanisms, individual strategies
references	a large body of literature	Selous (1931), Gueron et al. (1996), Prins (1996), Couzin & Krause (2003), Couzin et al. (2005), Ballerini et al. (2008), Hemelrijk & Hildenbrandt (2008), Conradt & Roper (2009) and Conradt et al. (in press)
group decision	traffic movements	job allocation in eusocial insects
perspective	individual behaviours	individual decisions
references	Couzin & Krause (2003) and Ishaque & Noland (2008)	Beshers & Fewell (2001)
group decision	panic behaviour in crowds	nest choice in eusocial insects
perspective	individual strategies	behaviour of individual scouts
references	Aube & Shield (2004)	Seeley & Buhrman (1999), Franks et al. (2009), List et al. (2009) and Sumpter & Pratt (2009)
decision category: aggregate/consensus decisions
group decision	consumer choice	movements in large groups
perspective	market prices	speed, accuracy, patterns
references	a large body of literature	Wallraff (1978), Krause et al. (1992), Reebs (2000), Couzin & Krause (2003), Simons (2004), Couzin et al. (2005), Buhl et al. (2006) and Dyer et al. (2009)
group decision	panic behaviour in crowds	nest choice in eusocial insects
perspective	evacuation time	decision speed and accuracy
references	Helbing et al. (2000)	List et al. (2009) and Sumpter & Pratt (2009)