Table 4. The Probability of Switching to Defection regressed against % Cooperating Neighbors in Previous Round, with Interactions.

	(1)	(2)	(3)	(4)
	Fixed	Viscous	Fluid	All conditions
% Cooperating Neighbors in Previous Round	−1.405	0.425	−0.669	−1.225
	(0.919)	(1.254)	(1.127)	(0.765)
Current Round Number	0.090	0.563***	0.494**	0.178**
	(0.057)	(0.104)	(0.243)	(0.079)
Number of Neighbors in Previous Round	−0.371	−0.111	−0.186***	−0.146***
	(0.240)	(0.130)	(0.044)	(0.047)
Number of Neighbors in Current Round	0.464**	0.047	0.113**	0.113***
	(0.225)	(0.125)	(0.046)	(0.040)
% Cooperating Neighbors * Round Number	−0.236	−1.104***	−0.481	−0.417**
	(0.153)	(0.321)	(0.362)	(0.164)
Membership in the fluid condition				−1.028
				(0.840)
Fluid Condition × % Cooperating Neighbors				0.385
				(1.398)
Fluid Condition × Round Number				0.266
				(0.248)
Fluid Condition × % Cooperating Neighbors × Round Number				−0.041
				(0.389)
Constant	−0.486	−1.140	−1.229	−0.236
	(0.576)	(0.889)	(0.793)	(0.459)
Observations	377	356	494	1,227

Robust standard errors in parentheses.

^***p<0.01,

^**p<0.05,

^*p<0.1.

This table shows the results from logistic regressions with interaction terms predicting the probability of defecting in the current round, among individuals who cooperated in the previous round (i.e. predicting the spread of defection). We report the coefficients and robust standard errors clustered on subject and session for each independent variable, and include interactions between variables.