There is a long-standing unresolved debate in game theory and experimental economics regarding the behavioral equivalence of the direct-response method (hot play) and the strategy method (cold play). Using a unified experimental framework, we compare behavior elicited via both methods in four different Centipede Games that differ in their incentives to take or pass, in the evolution of those incentives over decision nodes, and in the asymmetry of the incentives across the two player roles. Out of the four Centipede Games, we find that both methods yield statistically different behavior in two of them, while in the remaining two we cannot reject the same behavior across the hot and cold methods. Whenever the behavior diverges, hot play consistently makes individuals stop earlier. These findings should shift the question from whether both methods are generically behaviorally equivalent to under which conditions they are (not) and why.

The strategy method (SM) is, in practice, subject to a possibly severe economic-theoretical bias. Although many studies utilize SM to examine responses to rare or off-equilibrium behaviors unattainable through direct elicitation (DE), they ignore the fact that the strategic equivalence between SM and DE holds for the monetary payoff game but not the game participants actually play, which is in terms of utilities. We report three results. First, failing to account for estimation bias when decisions at one information set can influence utility at another may result in significant differences in decision-making. Second, the magnitude of this bias can be substantial, comparable to other measured treatment effects. Third, minor interventions targeting salience can amplify these differences similarly, causing treatment effects to differ significantly between SM and DE, even reversing in direction. These findings emphasize the need for reconsideration of the SM’s reliability for economic research.

This article highlights a potential and significant economic–theoretical bias in the widely used strategy method (SM) technique. Although SM is commonly employed to analyze numerous observations per subject regarding rare or off-equilibrium behaviors unattainable through direct elicitation (DE), researchers often overlook a critical distinction. The strategic equivalence between SM and DE is applicable in the context of monetary payoff games, but not in the actual utility-based games played by participants. This oversight may lead to inaccurate conclusions and demand a reevaluation of existing research in the field. We formalize the mapping from the monetary payoff game to this actual game and delineate necessary and sufficient conditions for strategic equivalence to apply.

According to the theory of guilt aversion, agents suffer a psychological cost whenever they fall short of other people’s expectations. In this paper, we suggest that there may be limits to this kind of motivation. We present evidence from an experimental dictator game showing that behavior is consistent with guilt aversion for relatively low levels of recipient expectations, roughly up to the point where the recipient expects half of the available surplus. Beyond that point the relationship between expectations and transfers becomes negative. Moreover, we examine this relationship at the individual level and establish a typology of subjects depending on how and whether they condition their behavior on recipient expectations.

Conditional cooperation is the tendency to cooperate if and only if others do so as well. It is the most common behavior in social dilemmas. We study how the incidence of conditional cooperation in the public goods game, the most widely studied social dilemma in experimental economics, varies with group size. In a laboratory experiment, we apply the strategy method to elicit how participants’ willingness to contribute to a public good depends on other group members’ decisions. A within-subject design allows us to evaluate and compare an individual participant's contribution behavior in different-sized groups. Two main findings emerge. First, the share of players who are conditional cooperators is consistent across group sizes. Second, the strategies chosen imply that conditional cooperators hold a (correct) belief that others are more cooperative in a larger than in a smaller group.

The strategy method is a powerful method for eliciting conditional cooperation instrategic interactions. Theoretically, players’ cooperation conditionalon a specific level of others’ cooperation using the strategy methodshould be equal to their unconditional cooperation given an equivalent beliefabout others’ cooperation. However, using the Prisoner’s Dilemma,we show that decisions using the strategy method are more selfish than decisionsunder a simultaneous decision protocol predicted from players’ beliefs.This is driven entirely by lower cooperation among conditional cooperators withlow expectations about others’ cooperation. We further show that relativeto simultaneous choice, the strategy method shifts salient norms from anegalitarian fairness norm (‘give half’) to a reciprocity norm(‘match others’ behaviour’). This undermines cooperationamong players with low beliefs about others’ cooperation. These resultsthus show that the strategy method does not merely hold beliefs constant, butalso shifts which salient norms influence choice behaviour. This has importantimplications for the use of the strategy method in eliciting socialpreferences.