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This paper replicates four highly cited, classic lab experimental studies in the provision of public goods. The studies consider the impact of marginal per capita return and group size; framing (as donating to or taking from the public good); the role of confusion in the public goods game; and the effectiveness of peer punishment. Considerable attention has focused recently on the problem of publication bias, selective reporting, and the importance of research transparency in social sciences. Replication is at the core of any scientific process and replication studies offer an opportunity to reevaluate, confirm or falsify previous findings. This paper illustrates the value of replication in experimental economics. The experiments were conducted as class projects for a PhD course in experimental economics, and follow exact instructions from the original studies and current standard protocols for lab experiments in economics. Most results show the same pattern as the original studies, but in all cases with smaller treatment effects and lower statistical significance, sometimes falling below accepted levels of significance. In addition, we document a “Texas effect,” with subjects consistently exhibiting higher levels of contributions and lower free-riding than in the original studies. This research offers new evidence on the attenuation effect in replications, well documented in other disciplines and from which experimental economics is not immune. It also opens the discussion over the influence of unobserved heterogeneity in institutional environments and subject pools that can affect lab results.

This paper replicates and refines the finding that subsidies for charitable contributions of a rebate type are less effective than matching subsidies. A survey based field experiment with health charities was conducted among a national sample representative of the Dutch population on key demographic characteristics. The greater effectiveness of matching subsidies found in laboratory experiments is replicated. Also some evidence is provided on why matches are more effective than rebates. Matches attract a larger pool of donors, in part because donors expect more people to make donations and “join in.” Matches also increase the amount contributed among the higher educated, higher income households and larger donors. Subsidies of either type do not decrease subsequent giving in a campaign for tsunami relief. The experiment could not test whether the greater effectiveness of a matching subsidy is due to a change in the donor’s attention to the benefits of a donation to the cause. This explanation should be tested in future research. The findings imply that a given budget available to subsidize charitable contributions can be used more effectively if the subsidy is framed in the form of a match than in the form of a rebate. Nonprofit organizations can use this insight in the design of fundraising campaigns. For governments the finding suggests that the effectiveness of current subsidies for charitable contributions can be enhanced by matching them rather than providing a deduction in the income tax, which works as a rebate.

Shang and Croson (2009) found that providing information about the donation decisions of others can have a positive impact on individual donations to public radio. In this study, we attempted to replicate their results, but found no evidence that social information affected donation decisions. However, most of our donors were renewing members, a group which Shang and Croson also found was not influenced by social information.

The Wikipedia (2008) entry for mathematical sociology cites four books with ‘mathematical sociology’ in the title: Coleman (1964), Fararo (1973), Leik and Meeker (1975) and Bonacich (2008). Fararo (1973, pp. 764–766) provides a guide to the literature in mathematical sociology covering journals, bibliographies, reviews and expository essays, readers, texts, original monographs and research papers. Many of the references are either broader than mathematical sociology, for example, concerning the behavioural sciences in general, or narrower, dealing with a particular topic within sociology, or concerning a related field such as social psychology. Three classical original monographs are identified: Dodd (1942), Zipf (1949) and Rashevsky (1951). Included in a second generation of monographs is Coleman's (1964) ‘An Introduction to Mathematical Sociology’. Could it be that this is the first use of the phrase ‘mathematical sociology’?

The central bank policy instruments have become less effective in an environment where economies are integrated with sophisticated financial products. We argue that economic stability is a function of interactions between financial and commodity markets. We utilize MGARCH models to identify volatility comovements between these markets in the United States since 2000. Our results suggest that financial markets have strong impacts on prices and volatility in commodity markets which could be due to intertemporal capital mobility. Thus, understanding commodity markets is inseparable from understanding financial market activities, and must now be included in an economic equation to achieve an effective policy.