Panel GMM Research Articles

Guaranteed Student Loans and Subsidies: Who Captures the Rents?

The paper analyzes effects of borrower interest rates and student lender subsidies on federally guaranteed student loan volumes from 1988 to 1994 and from 1996 to 2006. In present and past policy debates, some have contended that lender subsidy cuts would cause some lenders to reduce loan supply or to leave the student loan market. A simple model of the student loan market suggests that if lenders receive economic rents due to overly generous subsidies, small changes in subsidy levels should not affect loan supply. The empirical results based on a variety of GMM panel estimators find evidence of a link between higher SAP margins and higher loan volumes is weak or inconclusive for both the 1988-1994 and 1996-2006 periods. This suggests that subsidy reductions had no discernable effect on student loan volumes. Results also suggest that higher real borrower interest rates reduce student loan volumes for public colleges and universities.

Agglomeration and growth: Cross-country evidence

We investigate the impact of within-country spatial concentration of economic activity on country-level growth, using cross-section OLS and dynamic panel GMM estimation. Agglomeration is measured alternatively through urbanization shares and through indices of spatial concentration based on data for sub-national regions. Across estimation techniques, data sets and variable definitions, we find evidence that supports the “Williamson hypothesis”: agglomeration boosts GDP growth only up to a certain level of economic development. The critical level is estimated at some USD 10,000, corresponding roughly to the current per-capita income level of Brazil or Bulgaria. Hence, the tradeoff between national growth and inter-regional equality may gradually lose its relevance. Our results also imply that, in terms of foregone growth, the cost of policies that inhibit economic agglomeration is highest in the poorest countries.

Crises and human capital accumulation

Abstract. This paper studies the effects of crises on human capital formation. Theoretically, a crisis undermines total factor productivity, which reduces the return to working and to accumulating physical capital. If the crisis is temporary, young agents will study now and work later. Human capital rises. To test our model we rely on inflation crises as our main empirical proxy. Using GMM panel procedures, our analysis for 86 countries in 1970–2000 confirms the positive effects of crises on human capital. Our main findings survive several robustness tests. JEL classification: E31, D90

Estimating a Small DSGE Model under Rational and Measured Expectations: Some Comparisons

Using European panel data and GMM system estimation, we explore the empirical performance of the standard three-equation New Keynesian macro model under different informational assumptions. As a benchmark, we consider the performance of the model under rational expectations and revised (final) data. Alternatively, instead of imposing rational expectations hypothesis we use realtime information, ie Consensus Economics survey data, to generate empirical proxies for expectations in the model and the current output gap in the Taylor rule. We demonstrate that, contrary to the assumption of rational expectations, the errors in measured expectations and real-time current output gaps are positively autocorrelated. We produce evidence that the use of real-time variables (including measured expectations) improves the empirical performance of the New Keynesian model. Relaxation of the rational expectations hypothesis makes a noticeable difference for the parameters of the New Keynesian model, especially in the Taylor rule.

The beta puzzle revisited: A panel study of hedge fund returns

Ferson and Schadt (1996) observed a beta puzzle in the mutual fund industry, which is a negative link between their beta and the market risk premium. The objective of this study is to verify if such a relation is present in the hedge fund industry. Our contribution is threefold. First, we use an instrumental variable method to estimate our conditional version of the Fama and French (F&F) model, conditional models being usually estimated by ordinary least squares. Secondly, we resort to a new set of performing instruments to estimate our conditional model: the higher moments of the risk factors that constitute the augmented version of the F&F model. Finally, we resort to a GMM panel procedure to estimate the excess returns of the HFR hedge funds pooled by strategy over the period 1997–2005. Our study reveals that there is generally no beta puzzle in the hedge fund industry. There is an apparent beta puzzle for the distressed securities and short seller strategies, but it seems rational for those strategies to increase their beta when the market risk premium is low: business opportunities are then much more important for them.

Earning Forecast Error in US and European Stock Markets

The paper investigates the dynamics and determinants of the earning forecast bias in two (US and Eurozone) stock samples matched by size and industry affiliation. Evidence is found that the European bias is significantly higher in absolute terms, irrespective of the year and the distance from the release date, with the exception of the 1997–2000 period in which US stocks are more optimistically valued. Cross-market differences persist when they are regressed, in a panel GMM estimate, on various controls such as the number of individual forecasts and their standard deviation for any considered stock, with the latter being significantly lower in the US market. Finally, it is observed that a convergence process is at work in both markets, with the bias becoming progressively lower as the release date gets closer.

Effects of Innovation on Employment: A Dynamic Panel Analysis

This paper estimates the effect of innovation on employment at the firm level. Our uniquely long innovation panel data set of German manufacturing firms covers more than 20 years and allows us to use various innovation measures. We can distinguish between product and process innovations as well as between innovation inputs and innovation outputs. Using dynamic panel GMM system estimation we find positive effects of innovation on employment. This result is robust to the use of product and process innovations as well as for innovation input and output.

Opportunity or necessity? The spatial determinants of entrepreneurship in South Africa

In South Africa's mainly rural provinces, the lack of entrepreneurial activity may be due to the lack of opportunities or the lack of ability to engage in opportunities. If the latter is the case, then one would predominantly see entrepreneurial activity arise out of necessity. To find an empirical answer to the question, we focus on the determinants of profits and profit rates across the magisterial districts of these two provinces. We use panel data across 50 magisterial districts from 1996 to 2001, in both a simple OLS model as well as a one-step GMM panel data model, to find that profits are higher in those districts with higher levels of educational attainment. Profits are also high where the informal sector is smaller. This suggests that the informal sector attracts mainly necessity entrepreneurs. The findings in this paper are also consistent with a situation wherein those unemployed from the rural areas migrate towards urban areas to join the informal sector in those areas. This kind of migration depresses profit rates in these urban areas.

Are Indian States Converging in the Post-Reform Period?: An Empirical Inquiry

This paper studies the convergence phenomenon for 23 states of India for the period 1981 to 2001. The decades of the 1980s and the 1990s has been studied separately to comment on the convergence behaviour in the pre reform and post reform period. In addition to that of per capita SDP, convergence of per capita output emanating from the agriculture, industry and the services sector has been analysed to get a deeper insight. Both sigma (σ) convergence and beta (β) convergence have been examined. The study finds absence of sigma (σ) convergence and unconditional beta (β) convergence of per capita NSDP both in the 1980s and 1990s. However, conditional beta (β) convergence estimates reveal that the poorer states are catching up with their richer counterparts in the 1990s. The panel GMM estimates reveal that Indian states converged to their steady state output at a higher rate in the 1990s compared to the 1980s. At the sectoral level, Industry had a higher speed of convergence than agriculture in both decades. Further, divergence rather than convergence is observed for the services sector in both decades.

Entry, exit and productivity growth: Spanish manufacturing during the eighties

This paper analyses the role played by both competitive pressure (increasing imports) and the restructuring of industries through entry and exit in productivity growth of Spanish manufacturing during the eighties, the key period of its accession to the EEC economy. A GMM panel estimation of the determinants of corrected Solow residual for 75 manufacturing during 1979-1990, shows that these forces accounted for 80% of productivity growth, playing an important role the displacement of inefficient firms by competitive entry.

Employee participation and productivity

This paper measures the productivity impact of shop-floor employee involvement. On the basis of a representative German establishment data set, the study finds that the introduction of teamwork and autonomous work groups, and a reduction of hierarchies in 1996/1997 significantly increased average establishment productivity in 1997–2000. The estimation strategy controls for unobserved invariant establishment heterogeneity by using a two-step system GMM panel regression approach. It simultaneously takes account of endogeneity of participative work organization by instrument variable regressions. It is also shown that the productivity effect of shop-floor employee involvement is stronger in establishments with works councils.

PATENTS, R&D, AND TECHNOLOGICAL SPILLOVERS AT THE FIRM LEVEL: SOME EVIDENCE FROM ECONOMETRIC COUNT MODELS FOR PANEL DATA

This paper analyses the relationship between the main determinants of technological activity and patent applications. To this end, an original panel of 181 international manufacturing firms investing substantial amounts in R&D during the late 1980s has been constructed. The number of patent applications by firms is explained by current and lagged levels of R&D expenditures and technological spillovers. Technological and geographical opportunities are also taken into account as additional determinants. In order to examine this relationship, several econometric models for count panel data are estimated. These models deal with the discrete nature of patents and firm specific unobservables arising from the panel data context. The main findings of the paper are first, a high sensitivity of results to the specification of patent distribution. Second, the estimates of the preferred GMM panel data method suggest decreasing returns to scale in technological activity and finally a positive impact of technological spillovers on firm's own innovation. © 1997 John Wiley & Sons, Ltd.