Cointegration and control: Assessing the impact of events using time series data

Control groups can provide counterfactual evidence for assessing the impact of an event or policy change on a target variable. We argue that fitting a multivariate time series model offers potential gains over a direct comparison between the target and a weighted average of controls. More importantly, it highlights the assumptions underlying methods such as difference in differences and synthetic control, suggesting ways to test these assumptions. Gains from simple and transparent time series models are analysed using examples from the literature, including the California smoking law of 1989 and German reunification. We argue that selecting controls using a time series strategy is preferable to existing data‐driven regression methods.     

Patterns of Investor-State Dispute Settlement Decisions

This paper examines the pattern of settlements, investor wins and state wins in investor-state dispute settlement cases, focusing on the impact of arbitration rules, the resources and experience of the litigants, the type of treaty breach under investigation, and the pattern of state intervention. Logistic regression results show that settlements are more likely when investors do not disclose their allegations publicly, when the host state has been involved in a greater number of past cases, and when the respondent state has a higher control-of-corruption rating. Panel awards to investors are more likely in cases of alleged direct expropriation and less likely for indirect expropriation. Panel decisions favoring the state increase with higher per capita income and rule-of-law ratings.     

Liking what others “Like”: using Facebook to identify determinants of conformity

In this paper we explore the micro-level determinants of conformity. Members of the social networking service Facebook express positive support to content on the website by clicking a Like button. We set up a natural field experiment to test whether users are more prone to support content if someone else has done so before. To find out to what extent conformity depends on group size and social ties we use three different treatment conditions: (1) one stranger has Liked the content, (2) three strangers have Liked the content, and (3) a friend has Liked the content. The results show that one Like from a single stranger had no impact. However, increasing the size of the influencing group doubled the probability that subjects expressed positive support. Friendship ties were also decisive. People were, on average, four times more likely to press the Like button if a friend, rather than a stranger, had done so before them. The existence of threshold effects in our experiment clearly shows that both group size and social proximity matters when opinions are shaped.     

Cuba,Trade Dependency and the GATT/WTO System

Cuba sought economic independence from the U.S. and its reliance on sugar exports after its 1959 revolution, but subsequently developed new dependency relationships. In the meantime, Cuba remained inside the General Agreement on Tariffs and Trade (GATT), despite conducting most of its trade outside it. This paper explores the political economy of Cuba’s participation in the GATT and later the World Trade Organization (WTO). Documents show that Cuba sought to use its participation to gain new markets and influence in the developing world. While Cuba has gained little economically from its participation, in recent years it has diversified its exports and trade partners, and its trade interests now align more closely with WTO rules. Economic reforms will be necessary in order for Cuba to benefit.     

Competition and cooperation in the exploitation of the groundwater resource

We study the exploitation of a common groundwater resource, first as a static and then as a differential game, in order to take into account the strategic and dynamic interactions among the users of the resource. We suppose that firms can form coalitions or can decide not to cooperate. The non-cooperation regime is characterized by pumping that lead to depletion of the aquifer; the cooperation preserves the resource. Open-loop and feedback equilibria have been computed and compared in order to characterize the existence of cooperators and defectors in water resources management.     

Capital gains lock-in and governance choices

Differences in accrued gains and investors’ tax-sensitivity induce variation in a capital gains lock-in effect across mutual funds even for the same stock at the same time. Exploiting this variation, we show this effect influences funds’ governance decisions: higher capital gains decrease the likelihood a fund exits prior to contentious votes and increase the likelihood a fund votes against management. Consistent with tax motivation, these findings are concentrated among funds with tax-sensitive investors. Further, high aggregate capital gains across funds holding a stock predict a higher likelihood management loses a vote and a lower likelihood a contentious vote is proposed.     

The scope and scale of the informal food economy of South African urban residential townships: Results of a small-area micro-enterprise census

Growing urbanisation in South Africa is reflected in burgeoning Working class and informal township settlements on the fringes of its major towns and cities. Paired with this is an increasing reliance on cash as the primary means of economic transaction, which has in turn stimulated the growth of micro-enterprise business activities within the township context. This article discusses the findings of an eight-township small-area census which occurred between 2010 and 2013 in Cape Town, Johannesburg, Ekurhuleni and Durban townships representing 250 000 residents. The researchers were able to establish the scope and scale of informal food and drink retailing in these localities. Of the 10 049 micro-enterprises located in the study, some 3966 (or 39% of the total) trade in food. These include enterprises in primary production, fresh produce retailing, grocery retailing from house and spaza shops, and informal foodservice enterprises. Food is the basis for much township informal business and plays an important role in making food increasingly affordable and locally accessible, and in creating cash employment. The article builds on the knowledge base of the township informal economy role in bolstering food security needs for the marginalised.