Research

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Publication

Estimation of Technical Change: Direct Semi/nonparametric Approaches

with S. C. Kumbhakar and S. Zhao, Economics Letters, 199, Article 109734

This paper introduces some novel approaches to formulate and estimate technical change nonparametrically in a variety of cases without estimating the underlying production technology usually specified by a production, cost, revenue or transformation function. The binding theme in all these formulations of technical change is the use of first-order conditions of profit maximization and cost minimization. The technical change measures are observation-specific due to their nonparametric nature.

Working Papers

Does Subsidy Increase Firm Productivity? Evidence from Chinese Manufacturing Enterprises

with M. Jin and S. C. Kumbhakar, under review, Job Market Paper

This paper examines the effect of government subsidy on firm-level productivity. The subsidy-promoting policies are oftentimes justified on the ground that subsidy increases the recipient firms' innovation and productivity. We develop a novel (semiparametric) method to structurally identify the firm-level productivity in the presence of subsidy. Unlike previous studies, we assume that subsidy is endogenous. To correct for the endogenous problem we use a switching regression in our semiparametric production function. Our method provides an improved framework for estimating the production function with endogenous and/or censored variables. We apply our method to study the effect of subsidy on firm-level productivity in Chinese machinery industry, using a panel data from 1998 to 2007. We find strong empirical evidence that subsidy has a positive effect on firms' persistent productivity. We also carry out a decomposition analysis to separately examine the subsidy effect on output via the input productivity channel and the persistent productivity channel. Opposite effects are found from the two channels and overall subsidy has a mild positive effect on a firm's output.

Do Subsidies Matter in Productivity and Profitability Changes? The Case of Norwegian Agriculture

with S. C. Kumbhakar and G. Lien, under review

In this paper, we use both parametric and nonparametric approaches to estimate total factor productivity (TFP) and profitability changes, and decompose these changes into their various components. An important concern in the decomposition exercise is to examine the contribution of subsidies. In both the parametric and nonparametric approaches, we consider estimation methods treating the subsidy as either exogenous or endogenous. Furthermore, we evaluate each of these models with and without inefficiency. Thus, we have parametric (nonparametric) models with the endogenous (exogenous) treatment of subsidies with (and without) inefficiency, eight different models in total. We employ a panel of Norwegian farms producing multiple outputs to highlight our methods, and a production technology represented by an input distance function to handle the multiple outputs. Our objective in using eight different models is to examine the robustness of subsidies and the other components of TFP change. These components relate to technical change, scale economies, subsidies, input and output misallocations, and inefficiency. In addition to the TFP change components, profitability change involves two extra components, i.e., the changes in input and output prices.

Trade and Productivity in the Presence of Subsidy: A Firm Level Analysis

This paper investigates the relationship between trade status and productivity with consideration of governmental subsidies at the firm level. The previous literature has documented that international trade does affect a firm's productivity in different ways. Firms which import tend to have a higher productivity than those who only use inputs produced domestically. Export behavior also benefits firms in terms of producing more efficiently. Two-way traders who both import and export typically enjoy a trading premium when generating a higher level of output. In addition to reexamining the trade-production linkage, we involve governmental subsidies into the analysis because subsidies are important in a firm's production process. Using a combined data set of computer and peripheral industry from China, we find that on average trading is beneficial to the production outcome of manufacturing firms. However, the effect of subsidies within this association depends on the subsidized amount and an extremely high subsidy might harm a firm's trade-production premium.

Do Institutions Matter for Economic Growth?

under review

Using a unique data set assembled from several sources, we examine the effects of democracy, corruption, and economic freedom on economic growth for over one hundred countries. To allow for heterogeneous effects, we use a quantile regression approach. Our results support some findings in the literature, but also provide some new conclusions. In many cases, quantile regression estimates are quite different from those from GMM. We find that the positive effect of democracy is lower for the countries with a higher growth rate of GDP per capita, which may sound counter-intuitive to conventional wisdom. Likewise, we find that corruption "sands the wheels" ("greases the wheels") for the lowest (highest) GDP per capita growth countries. Economic freedom shows a positive effect on GDP per capita growth rate. Our results suggest that since democratic status is hard to change in the short run, certain current corruption control measures as well as economic freedom adjustment policies may be reconsidered, especially among the fastest and slowest growing countries.

Heterogeneous Effects of Income on Democracy under Different Colonizers - Comment on Income and Democracy: Comment

with S. C. Kumbhakar

This paper undertakes both a narrow and wide replication of the heterogeneity in effects of income on democracy considered by Cervallati et al. (2014). By further dividing the sample, we show that within colonies, the effects of income on democracy vary: statistically negative for the former French, British, German, and Danish colonies, but statistically insignificant for the other colonies. Contrary to their conclusion, there is no statistical evidence that the heterogeneous effects are related to colonial history and early institutions. Our findings are robust to the use of estimation techniques.

Export and Productivity: A Semiparametric Smooth Coefficient Approach

with S. C. Kumbhakar

To a large extent, productivity drives economic well-being of a society. The major literature shares a common perspective that there exists a positive linkage between firm's export behavior and productivity level for most countries. However, researchers have found that firms in China show a negative export premium of productivity. In this project, we revisit the the export-productivity puzzle in the Chinese manufacturing sectors. We use firm age, size, location and ownership as factors affecting export assignment. The potential endogeneity of export is formally tested and confirmed with a testing device. This endogeneity is therefore taken care of using a recently proposed estimation procedure. We utilize the Chinese Industrial Enterprises Database which is an unbalanced panel data spanning from 1998 to 2007 to carry out our analysis. In this paper, we limit the discussion to manufacturing firms only since they are most relevant to productivity study. We find that exports decrease output/productivity in the Chinese manufacturing industries, which echoes with the previous studies.

Work in Progress

Technical and Productivity Changes

with S. C. Kumbhakar