More educated parents are observed to have better educated children. From a policy point of view, however, it is important to distinguish between causation and selection. Researchers trying to control for unobserved ability have found conflicting results: in most cases, they have found a strong...

This paper examines panel data modelling with latent variables in analyzing log-linear relations between inputs and output of firms. Our particular focus is on (i) the "increasing returns to scale puzzle" for labour input and (ii) the GMM estimation in the context of errors-in-variables and...

An applied econometric study of aggregation, based on an unbalanced panel data set for manu-facturing plants is presented. Panel data are informative in examining aggregation of variables, parameters, and relationships empirically since they (i) allow estimation at both the micro and the macro...

Several studies, conducted on U.S. data, have found rather strong income responses to changes in marginal tax rates, when treating tax reforms as "natural experiments" and applying the differences-of-differences estimator on individual income data. The Norwegian tax reform of 1992 implied...

We evaluate consequences of some important assumptions ofthe perpetual inventory method of capital stock calculation under geometric depreciation. The data are plant-level panel data from the Norwegian manufacturing statistics, containing independent measures of capital stocks and gross...

Galí, Gertler and Lòpez-Salido (2005), GGL, assert that the hybrid New Keynesian Phillips curve, NPC, is robust to different choices of estimation procedure and so some forms of specification bias. Specifically, the dominance of forward-looking behavior is robust according to GGL. We assess...

This paper discusses identification, estimation and testing in panel data models with attrition. We focus on a situation which often occurs in the analysis of firms: Attrition (exit) is endogenous and depends on the outcomes of an observed stochastic process and the interest-parameters...

The hypothesis of market power in the Norwegian primary aluminium industry is tested using plant-level panel data. Economies of scale are found to be present, and Norwegian aluminium plants charge a procyclical price-cost margin that significantly exceeds zero. Consequently, the simple...

The generous Nordic model of welfare is commonly viewed as an exceptional success both in terms of equality and economic growth. However, it has recently become evident that subgroups of the population with weak labour market attachment and high welfare dependency, such as lone mothers, were...

This paper explores the inconsistency of common scale estimators when output is proxied by deflated sales, based on a common output deflator across firms. The problems arise when firms operate in an imperfectly competitive environment and prices differ between firms. In particular, we show that...