We experimentally explore the role of institutions imposing collective sanctions in sustaining cooperation. In our experiment, players only observe noisy signals about individual contributions in finitely repeated public goods game with imperfect monitoring, while total output is perfectly observed as it is often the case in collective action problems in society. We consider sanctioning mechanism that allows agents to commit to collective punishment in case the level of cooperation among members of society falls short of a target. We find that cooperation is higher with collective punishment compared to both no punishment or punishment targeting individuals. Importantly, our results indicate that it is the combination of making a commitment to be punished and the collective nature of punishment which induces cooperation. Our findings show that punishing a group collectively for misbehavior of some of its members induces cooperation when individuals participate in setting up the sanctioning institution. The study contributes to the literature on institutional legitimacy and how to ensure good government performance when dealing with collective action problems, and, by considering commitment, improves enforcement methods criticized for their detrimental effects on some societal groups.

This study examines the second language acquisition of Spanish past tense morphology by three groups of English speakers (beginners, intermediates and advanced). We adopt a novel methodological approach – combining oral corpus data with controlled experimental data – in order to provide new evidence on the validity of the Lexical Aspect Hypothesis (LAH) in L2 Spanish. Data elicited through one comprehension and three oral tasks with varying degrees of experimental control show that the emergence of temporal markings is determined mainly by the dynamic/non-dynamic contrast (whether a verb is a state or an event) as beginner and intermediate speakers use Preterit with event verbs but Imperfect mainly with state verbs. One crucial finding is that although advanced learners use typical Preterit–telic associations in the least controlled oral tasks, as predicted by the LAH, this pattern is often reversed in tasks designed to include non-prototypical (and infrequent) form–meaning contexts. The results of the comprehension task also show that the Preterit-event and Imperfect-state associations observed in the production data determine the interpretation that learners assign to the Preterit and the Imperfect as well. These results show that beginner and intermediate learners treat event verbs (achievements, accomplishments and activities) in Spanish as a single class that they associate with Preterit morphology. We argue that dynamicity contrasts, and not telicity, affect learners’ use of past tense forms during early stages of acquisition.