APPLICATION OF PANEL DATA MODELS IN BENCHMARKING ANALYSIS OF THE ELECTRICITY DISTRIBUTION SECTOR*

ABSTRACT ** : This paper explores the application of several panel data models in measuring productive efficiency of the electricity distribution sector. Stochastic Frontier Analysis has been used to estimate the cost‐efficiency of 59 distribution utilities operating over a nine‐year period in Switzerland. The estimated coefficients and inefficiency scores are compared across three different panel data models. The results indicate that individual efficiency estimates are sensitive to the econometric specification of unobserved firm‐specific heterogeneity. This paper shows that alternative panel models such as the ‘true’ random effects model proposed by Greene (2005) could be used to explore the possible impacts of unobserved firm‐specific factors on efficiency estimates. When these factors are specified as a separate stochastic term, the efficiency estimates are substantially higher suggesting that conventional models could confound efficiency differences with other unobserved variations among companies. On the other hand, refined specification of unobserved heterogeneity might lead to an underestimation of inefficiencies by mistaking potential persistent inefficiencies as external factors. Given that specification of inefficiency and heterogeneity relies on non‐testable assumptions, there is no conclusive evidence in favour of one or the other specification. However, this paper argues that alternative panel data models along with conventional estimators can be used to obtain approximate lower and upper bounds for companies' efficiency scores.     

The effect of inflation on growth

The paper examines the effect of inflation on growth in transition countries. It presents panel data evidence for 13 transition countries over the 1990–2003 period; it uses a fixed effects panel approach to account for possible bias from correlations among the unobserved effects and the observed country heterogeneity. The results find a strong, robust, negative effect on growth of inflation or its standard deviation, and one that appears to decline in magnitude as the inflation rate increases, as seen for OECD countries. And the results include a role for a normalized money demand in affecting growth, as well as for a convergence variable, a trade variable and a government share variable. Robustness of the baseline single‐equation model is examined by expanding this into a three‐equation simultaneous system of output growth, inflation and money demand that allows for possible simultaneity bias in the baseline model.     

Euler equation errors

The standard, representative agent, consumption-based asset pricing theory based on CRRA utility fails to explain the average returns of risky assets. When evaluated on cross-sections of stock returns, the model generates economically large unconditional Euler equation errors. Unlike the equity premium puzzle, these large Euler equation errors cannot be resolved with high values of risk aversion. To explain why the standard model fails, we need to develop alternative models that can rationalize its large pricing errors. We evaluate whether four newer theories at the vanguard of consumption-based asset pricing can explain the large Euler equation errors of the standard consumption-based model. In each case, we find that the alternative theory counterfactually implies that the standard model has negligible Euler equation errors. We show that the models miss on this dimension because they mischaracterize the joint behavior of consumption and asset returns in recessions, when aggregate consumption is falling. By contrast, a simple model in which aggregate consumption growth and stockholder consumption growth are highly correlated most of the time, but have low or negative correlation in severe recessions, produces violations of the standard model's Euler equations and departures from joint lognormality that are remarkably similar to those found in the data.     

消费习惯、异质偏好与动态资产定价:纯交换经济情形

本文用Chan和Kogan、Bask和Cuoco等的方法考虑纯交换经济下的定价问题,我们引进了两个投资者:一个具有外在性消费习惯;一个不具有消费习惯。我们重点考察消费习惯对投资者的最优消费规则的影响以及对资产价格的确定。此外,我们还考虑了对数效用函数下,消费习惯以差的形式出现的情形下的消费规则和定价问题。我们发现当两个投资者中一个具有消费习惯而另一个不具有该习惯时,消费习惯同时改变两个投资者的最优消费规则、消费动态和财富动态。此时的动态资产定价受外在性消费习惯的影响,即时Sharpe比为常数,并等于同质量经济下的即时Sharpe比。同时,如果考虑对数效用函数下消费习惯以差的形式出现,则即时Sharpe比是时变的,反周期的。     

Asset pricing in an Islamic economy

ABSTRACT

We define an Islamic economy as one with borrowing restrictions, no leverage, and no risk-free asset. We derive a consumption-based asset pricing model for this economy under standard preferences. We demonstrate that news to consumption growth is the main driver of Islamic financial markets, but the degree of borrowing constraints also affects the pricing of Islamic assets. Using Saudi Arabian data, simulations show that our model does a good job in matching the observed equity premium as well as the volatility of the market return. Our model implies that the price-dividend ratio predicts dividend growth, and as a result that prices are driven mainly by cash-flow news rather than by discount rate news. Empirical tests show that our model is consistent with the data.     

The relationship between healthcare expenditure and disposable personal income in the US states: a fractional integration and cointegration analysis

This paper analyses the empirical relationship between inflation and growth using a panel data estimation technique, multiple-regime panel smooth transition regression, which takes into account the nonlinearities in the data. By using a panel data set for 10 countries in the Southern African Development Community permitting us to control for unobserved heterogeneity at both country and time levels, we find that a statistically significant negative relationship exists between inflation and growth for inflation rates above the critical threshold levels of 12 and 32% which are endogenously determined. Furthermore, we remedy the cross-section dependence with the common correlated effects estimator.     

The earnings effects of health and health-related activities: a panel data approach

We investigate the effects of health and health-related habits on earnings in China using panel data to control for unobserved heterogeneity related to individual traits and job characteristics. Health-related habits include smoking cigarettes, drinking tea, frequency of drinking alcohol and physical exercising. We find a significant and large impact of health status on earnings, controlling for schooling, experience and the unobserved individual heterogeneity and job heterogeneity. We also find that smoking has a strong negative effect on earnings net of health status, while the estimated effects of other health-related activities are statistically insignificant.     

Population growth and economic growth: a reconsideration

The relationship between population growth and development has long been a controversial topic in the economic development literature. Early work by Hoover and Coale and more recent work by Blanchet suggest that high fertility suppresses per capita income growth. However, recent work by Kelley and Srinivasan are ambivalent about such a neo-Malthusian relationship between population growth and economic growth. The authors examine these conflicting positions. They emphasize that the rates of both population growth and income growth are endogenous variables within a general equilibrium framework. An endogenous growth model with endogenous fertility is then developed. It is found that when all exogenous variables are controlled for, there exists an inverse relation between population growth and economic growth. However, when some exogenous factors change, such as an improvement in technological progress, the relation becomes ambiguous. This suggests that the conflicting findings in the literature may be because of the presence of substantial heterogeneity in unobserved variables across countries and over time in cross-country panel data sets.     

The Effects of Macroeconomic Policies in a Mercantilist Economy

By introducing money and foreign exchange in the Zou (1997) model of mercantilism, the paper shows the effects of macroeconomic policies in mercantilist economies. It is shown that in the long run, consumption and foreign asset accumulation increases as a result of stronger mercantilist sentiments, permanent increases in the consumption tax, increases in the monetary growth rate and purchases of foreign bonds. In the short run, however, macroeconomic disturbances including the mercantilist sentiments, the monetary growth rate, and the consumption tax have negative effects on current consumption and positive effects on current foreign asset accumulation, while purchasing foreign bonds has positive effects on both current consumption and current foreign asset accumulation. The theoretical explorations may provide a theoretical structure for hoarding international reserves and export-led growth strategy utilized by emerging market economies.     

An analysis of the consumption risk and asset returns of Chinese residents

The research on the consumption-based asset pricing theory is limited to the developed capital markets. This paper seeks to extend the research to the Chinese developing capital market. It analyzes the dynamic relationship between the Chinese residents’ consumption, stock market returns and interest rates with the CCAPM. According to the analyses of this paper, the IV regression results are mixed. However, the data can fit the model relatively well, and the empirical results fail to reject the model. Thus, the results show that a relationship between the Chinese residents’ consumption growth rates and the asset returns does indeed exist, and that the consumption volatility risk could influence the asset returns.     

The complementarity between calls and messages in mobile telephony

This article estimates price elasticities of demand for mobile telephone calls and messages. We use panel data consisting of telephone bills to Portuguese mobile telephony consumers. In order to account for the unobserved individual heterogeneity and data censoring, we estimate a Tobit model for panel data with individual random effects. The demands for calls and messages are inelastic. Calls and messages are found to be complements.     

Using job changes to evaluate the bias of value of a statistical life estimates

This paper presents a new approach to obtaining unbiased estimates of the value of a statistical life (VSL) with labor market data. Investigating job changes, we combine the advantages of recent panel studies, allowing us to control for unobserved heterogeneity of workers, and conventional cross-sectional estimations, which are less affected by measurement error. We find a VSL of 6.1 million euros from pooled cross-sectional estimation, 1.5 million euros from the first-differences panel model and 2.0 million euros from the job-changer specification. Thus, ignoring individual heterogeneity causes overestimates of the VSL, whereas the attenuation bias in panel data models leads to underestimates of the VSL. Our results are less biased than former results and can be used to perform cost–benefit analyses of public projects aimed at reducing fatality risks, e.g., in the domains of environmental, health, or traffic policy.     

中国居民消费、习惯偏好与资产收益研究

习惯模型是行为资产定价理论的重要组成部分,该模型将经济主体的习惯因素纳入到资产定价之中,由此推进了消费资本资产定价理论的发展。习惯模型已经在欧美等国家和地区得到了广泛研究,而在资本市场蓬勃发展的中国则处于被人遗忘的尴尬境地。本文利用外在习惯偏好模型对我国居民消费、习惯偏好与资产收益进行分析。GMM结果是混合性的,模型可以较好地拟合数据,GMM结果无法否定外在习惯偏好模型,因而无法否定习惯因素在消费与资产收益分析中的重要性。     

基于效用成本风险异质性的消费资本资产定价模型

资产定价既是现代金融的核心,也是许多困惑之所在,其中最著名的就是股权溢价之谜和无风险利率之谜。本文对消费资本资产定价模型中的效用成本做了重新思考,引入"效用成本风险异质性"的概念,并将效用成本区分为"消费效用成本"和"风险效用成本"。在此基础上,本文提出了消费资本资产定价模型的新形式,并对股权溢价之谜和无风险利率之谜进行解释。     

Health care expenditure and income in the OECD reconsidered: Evidence from panel data

This paper reconsiders the long-run economic relationship between health care expenditure and income using a panel of 20 OECD countries observed over the period 1971–2004. In particular, the paper studies the non-stationarity and cointegration properties between health care spending and income. This is done in a panel data context controlling for both cross-section dependence and unobserved heterogeneity. Cross-section dependence is modelled through a common factor model and through spatial dependence. Heterogeneity is handled through fixed effects in a panel homogeneous model and through a panel heterogeneous model. Our findings suggest that health care is a necessity rather than a luxury, with an elasticity much smaller than that estimated in previous studies.     

A simple method for estimating unconditional heterogeneity distributions in correlated random effects models

I propose a general, simple approach to recovering an unconditional heterogeneity distribution when a conditional distribution has been estimated. The approach can be applied to cross section models and panel data models-both static and dynamic-with unobserved heterogeneity.     

Regional evidence on financial development, finance term structure and growth

The finance-growth nexus is a classic source of debate among economists. This paper offers regional evidence on this issue in order to determine whether it can fit the data on a 147-year-old economic union, Italy. By means of this approach the pooling of developed and developing countries in the same sample can be avoided. Both cross-sectional and panel data estimates appear to show that more finance generates more growth. Endogeneity does not bias the results to a significant extent, and the finance-growth nexus is robust to spatial unobserved heterogeneity. Spatial correlation in the residuals is rejected by the data. Economic growth appears to be favoured more by short-term than by long-term credit.     

Can Habit Formation Be Reconciled with Business Cycle Facts?

Many asset pricing puzzles can be explained when habit formation is added to standard preferences. We show that utility functions with a habit then gives rise to a puzzle of consumption volatility in place of the asset pricing puzzles when agents can choose consumption and labor optimally in response to more fundamental shocks. We show that the consumption reaction to technology shocks is too small by an order of magnitude when a utility includes a consumption habit. Moreover, once a habit in leisure is included, labor input is counterfactually smooth over the cycle. In the case of habits in both consumption and leisure, labor input is even countercyclical. Consumption continues to be too smooth. Journal of Economic Literature Classification Numbers: E13, E21, E32.     

Fiscal Policy in a Growing Economy with Financial Frictions and Firm Heterogeneity

This paper constructs a tractable model of endogenous growth with financial frictions and firm heterogeneity. We introduce factor income tax, consumption tax as well as the government consumption into the base model and explore the growth effect of fiscal policy. We show that from the qualitative perspective, the long‐run effects of fiscal actions in our model are similar to those obtained in the representative agent models. However, the quantitative impacts of fiscal policy on long‐run growth in our setting can be substantially different from those established in the model where agents are homogeneous and there is no financial frictions.     

PORTFOLIO BEHAVIOUR AND ASSET PRICING IN A CHARACTERISTICS FRAMEWORK

We have applied the characteristics model to the problem of portfolio behaviour and asset pricing. By defining assets in terms of characteristics, we generated individual demands for assets which depended on the prices of assets, the technological relationship between assets and asset characteristics, and the individual's preferences for different characteristics. In general, the characteristics model cannot be readily aggregated across individuals. However, when we assumed that the assets-characteristics technology had a simple form which was common to all individuals, market-clearing conditions could be used to derive an asset pricing model. Finally, we showed that the characteristics model provides a unified approach to the problem of preference-based portfolio behaviour and asset pricing. A number of existing models can be interpreted as characteristics models: the state-preference model, the parameter-preference model, the capital asset pricing model and the inter-temporal capital asset pricing model.