We propose to change the default P-value threshold for statistical significance from 0.05 to 0.005 for claims of new discoveries. T he lack of reproducibility of scientific studies has caused growing concern over the credibility of claims of new discoveries based on 'statistically significant' findings. There has been much progress toward documenting and addressing several causes of this lack of reproducibility (for example, multiple testing, P-hacking, publication bias and under-powered studies). However, we believe that a leading cause of non-reproducibility has not yet been adequately addressed: statistical standards of evidence for claiming new discoveries in many fields of science are simply too low. Associating statistically significant findings with P < 0.05 results in a high rate of false positives even in the absence of other experimental, procedural and reporting problems.For fields where the threshold for defining statistical significance for new discoveries is P < 0.05, we propose a change to P < 0.005. This simple step would immediately improve the reproducibility of scientific research in many fields. Results that would currently be called significant but do not meet the new threshold should instead be called suggestive. While statisticians have known the relative weakness of using P ≈ 0.05 as a threshold for discovery and the proposal to lower it to 0.005 is not new 1,2 , a critical mass of researchers now endorse this change.We restrict our recommendation to claims of discovery of new effects. We do not address the appropriate threshold for confirmatory or contradictory replications of existing claims. We also do not advocate changes to discovery thresholds in fields that have already adopted more stringent standards (for example, genomics and high-energy physics research; see the 'Potential objections' section below).We also restrict our recommendation to studies that conduct null hypothesis significance tests. We have diverse views about how best to improve reproducibility, and many of us believe that other ways of summarizing the data, such as Bayes factors or other posterior summaries based on clearly articulated model assumptions, are preferable to P values. However, changing the P value threshold is simple, aligns with the training undertaken by many researchers, and might quickly achieve broad acceptance.

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Expanding access to commercial credit is a key ingredient of financial development strategies. There is less consensus on whether expanding access to consumer credit helps borrowers, particularly when loans are extended at high interest rates. Popular skepticism about "unproductive," "usurious" lending is fueled by research highlighting behavioral biases that may induce overborrowing. We estimate the impacts of expanding access to consumer credit at a 200% annual percentage rate (APR) using a field experiment and follow-up data collection. The randomly assigned marginal loans produced significant net benefits for borrowers across a wide range of outcomes. There is also some evidence that the loans were profitable. (JEL D12, D14, G21, I32

Standard-Nutzungsbedingungen:Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden.Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen.Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. ABSTRACT Firms spend billions of dollars each year advertising consumer products in order to influence demand. Much of these outlays are on the creative design of advertising content. Creative content often uses nuances of presentation and framing that have large effects on consumer decision making in laboratory studies. But there is little field evidence on the effect of advertising content as it compares in magnitude to the effect of price. We analyze a direct mail field experiment in South Africa implemented by a consumer lender that randomized creative content and loan price simultaneously. We find that content has significant effects on demand. There is also some evidence that the magnitude of content sensitivity is large relative to price sensitivity. However, it was difficult to predict which particular types of content would significantly impact demand. This fits with a central premise of psychology-context mattersand highlights the importance of testing the robustness of laboratory findings in the field. Terms of use: Documents inJEL codes: D01, M31, M37, C93, D12, D14, D21, D81, D91, O12

Abstract.We provide evidence from field experiments with three different banks, that reminder messages increase commitment attainment for clients who recently opened commitment savings accounts. Messages that mention both savings goals and financial incentives are particularly effective, while other content variations such as gain versus loss framing do not have significantly different effects. Nor do we find evidence that receiving additional late reminders has an additive effect. These empirical results do not map neatly into existing models, so we provide a simple model where limited attention to exceptional expenses can generate under-saving that is in turn mitigated by reminders.