OPTIMAL FORECAST COMBINATION UNDER REGIME SWITCHING*

This article proposes a new forecast combination method that lets the combination weights be driven by regime switching in a latent state variable. An empirical application that combines forecasts from survey data and time series models finds that the proposed regime switching combination scheme performs well for a variety of macroeconomic variables. Monte Carlo simulations shed light on the type of data‐generating processes for which the proposed combination method can be expected to perform better than a range of alternative combination schemes. Finally, we show how time variations in the combination weights arise when the target variable and the predictors share a common factor structure driven by a hidden Markov process.     

The Impact of Cannabis Use on Health

Summary Chronic daily cannabis use has been shown to have long term harmful health effects, which in turn is expected to reduce labour market productivity. The evidence is less clear on the health impact of less frequent consumption, which is the more typical mode of use, and previous empirical studies fail to find robust evidence of an adverse impact of these modes of use on labour market productivity. This paper attempts to shed some light on this issue by directly estimating the impact of cannabis consumption in the past week and past year on health status using information on prime age individuals living in Australia. We find that cannabis use does reduce self-assessed health status, with the effect of weekly use being of a similar magnitude as smoking cigarettes daily. Moreover, we find evidence of a dose-response relationship in the health impact of cannabis use, with annual use having roughly half the impact of weekly use.Helpful comments on an earlier draft were received from Jan van Ours, Rosalie Pacula, two anonymous referees and participants at the 81st Annual Conference of the Western Economic Association International.     

Are There Differential Effects of Price and Policy on College Students’Drinking Intensity?

This article investigates the impact of campus bans on alcohol use and the price of alcohol on college students'drinking intensity. The impact of a campus ban on drinking appears to depend on the ability of students to substitute off-campus access to alcohol for on-campus access. Where few off-campus alternatives exist, campus bans reduce the odds that a student becomes a heavy drinker but have no impact on the odds of transitioning from abstainer to drinker. Where off-campus alternatives are more plentiful, campus bans are less effective. Increasing the price of alcohol appears to be equally effective at reducing the likelihood of drinking and heavy drinking. (JEL)     

Applying Burke’s Dramatic Pentad to scenarios

Describing the evolution of possible futures in the narrative form is widely practised. However, while stories are intuitively recognized, the ability to compose a comprehensible story is often difficult. Ambiguities or inconsistencies within a scenario-as-story are not simply aesthetic faults, but are failings which can weaken the use of the technique in a learning or decision-making process. This paper provides a working understanding of narrative as a particular kind of knowledge and proposes an adaptation of Kenneth Burke’s Dramatic Pentad as a way to explicitly capture this kind of knowledge within a scenario construction process.     

Explaining cross-country variations in the prevalence of informal sector competitors: lessons from the World Bank Enterprise Survey

To advance understanding of informal sector entrepreneurship, the aim of this paper is to evaluate and explain the cross-country variations in the prevalence of informal sector competitors. To do so, World Bank Enterprise Survey (WBES) data is reported from 142 countries. This reveals that 27% of formal enterprises view competition from the informal sector as a major constraint on their operations, although this varies from 72% of formal enterprises in Chad to no formal enterprises in El Salvador. To explain these cross-country variations, four competing theories are evaluated which variously view informal sector entrepreneurship and enterprise to be more prevalent when there is either: economic under-development (modernisation theory); high taxes and state over-interference (neo-liberal theory); too little state intervention (political economy theory), or an asymmetry between the laws and regulations of formal institutions and the unwritten socially shared rules of informal institutions (institutional theory). A multilevel probit regression analysis confirms the modernisation and institutional theories, but not the neo-liberal and political theories. Beyond economic under-development, therefore, it is not too much or too little state intervention that is associated with the prevalence of informal sector competition but rather, whether the laws and regulations developed by governments are in symmetry with the norms, values and beliefs of entrepreneurs. The paper concludes by discussing the theoretical and policy implications of these findings.