Spurious principal components

The principal component regression (PCR) is often used to forecast macroeconomic variables when there are many predictors. In this letter, we argue that it makes sense to pre-whiten the predictors before including these in a PCR. With simulation experiments, we show that without such pre-whitening, spurious principal components can appear and that these can become spuriously significant in a PCR. With an illustration to annual inflation rates for five African countries, we show that non-spurious principal components can be genuinely relevant in empirical forecasting models.     

Tax contracts and elections

In this paper we examine the impact of tax contracts as a novel institution on elections, policies, and welfare. We consider a political game in which three parties compete to form the government and voters may behave strategically. Parties have policy preferences about the level of public-good provision and benefit from perks when in office. A government raises taxes for both purposes. We show that tax contracts yield moderate policies and lead to lower perks by avoiding the formation of grand coalitions in order to win government. Moreover, in polarized societies they unambiguously improve the welfare of the median voter.     

BUILDING SOCIAL CAPITAL FOR SOCIAL ENTREPRENEURSHIP

ABSTRACT: By entrepreneurial combinations of voluntary resources, project means from public and private sources, commissions on contracts and other ways of financing, the youth house Fryshuset, with a great number of social activities for primarily young people in Stockholm, Sweden, has been able to allocate resources for establishing and expanding its activities. This development would not have been possible without struggle against established norms, values, traditions and institutions, not least the ‘close to monopoly’ that the public sector in practice was having on the fields in which Fryshuset emerged. Step by step, Fryshuset has built partnerships and alliances with public, private as well as civil actors. Expressed in a general way, Fryshuset has built a new social capital and created new norms and values. The aim of the paper is to investigate how Fryshuset has managed to build social capital through, and for entrepreneurial efforts aiming to facilitate young peoples’ development.     

Strategic Regulation Policy in the Internet

Some countries are importers while others are exporters of global backbone connectivity. At the same time, input components such as local access are non-traded. This paper analyzes a non-cooperative regulatory game between importing and exporting countries, assuming that the prices of both traded and non-traded inputs can be regulated. We show that exporting countries choose a more restrictive regulation of non-traded goods than importing countries do. We further show that a requirement of international non-discrimination may hurt importing countries, and give firms producing traded inputs incentives to invest in quality degradation.     

Estimating Transition Probabilities from a Time Series of Independent Cross Sections

This paper considers the implementation of a nonstationary, heterogeneous Markov model for the analysis of a binary dependent variable in a time series of independent cross sections. The model, previously considered by M offitt (1993), offers the opportunity to estimate entry and exit transition probabilities and to examine the effects of time-constant and time-varying covariates on the hazards. We show how ML estimates of the parameters can be obtained by Fisher's method-of-scoring and how to estimate both fixed and time-varying covariate effects. The model is exemplified with an analysis of the labor force participation decision of Dutch women using data from the Socio-economic Panel (SEP) study conducted in the Netherlands between 1986 and 1995. We treat the panel data as independent cross sections and compare the employment status sequences predicted by the model with the observed sequences in the panel. Some open problems concerning the application of the model are also discussed.     

On forecasting cointegrated seasonal time series

We analyze periodic and seasonal cointegration models for bivariate quarterly observed time series in an empirical forecasting study. We include both single equation and multiple equation methods for those two classes of models. A VAR model in first differences, with and without cointegration restrictions, and a VAR model in annual differences are also included in the analysis, where they serve as benchmark models. Our empirical results indicate that the VAR model in first differences without cointegration is best if one-step ahead forecasts are considered. For longer forecast horizons however, the VAR model in annual differences is better. When comparing periodic versus seasonal cointegration models, we find that the seasonal cointegration models tend to yield better forecasts. Finally, there is no clear indication that multiple equations methods improve on single equation methods.