The pace of the growth rate of the economy largely depends, inter alia, on the rate of growth of the productivity of the economic activities of different sectors, which in turn, depends mainly on the adoption of technological changes. Various models with different real variables have been specified underlying certain assumptions in the literature to estimate the partial and total factor productivities through linear, Cobb-Douglas, constant elasticity of substitution and translog production function approaches in order to understand the production performance and resource use efficiency. In view of limited availability of resources it is essential to employ the resources efficiently, through substitution among the resources. The extent of substitution possibilities between the inputs in the industries is known through the estimates of the parameters by fitting constant elasticity of substitution and translog production functions to the time series data and cross-section data across the firms. The nature of returns to scale is also very imperative to know the responsiveness of the production to the changes in the inputs employed. All these aspects pertaining to productivity, substitution possibilities and returns to scale are concerned with production, inputs, returns to inputs and technology. The empirical studies particularly on productivity, substitution possibilities and returns to scale are being carried out using different specifications. The estimation of the economic relationship between factor (labor or capital or raw materials) productivity and its determinants, production and its determinants using time series data, particularly by econometric methods has to be carried out having ensured that time series variables included in the specification under consideration do not have unit root problem. If the time series variables have unit root problem, they need to be differenced until they become stationary. The unit roots tests are being carried out to determine the order of integration of each variable using Augmented Dicky-Fuller and Phillips and Perron tests. Though testing of the presence of unit root of the time series variables is convoluted one, with the advent of personal computers and software packages, the properties of the time series are being tested for commonsensical analysis. The computers are playing crucial role in carrying out effective academic research in all disciplines including Industrial Economics. The papers in this issue focus on application of the theory of market leaders and endogenous market structures, building a theoretical model to examine the tenderers' behaviors, relationship between labor productivity and wage rates, and estimation of total factor productivity.

Federico Etro in the paper, "Market Leaders, Antitrust Policy and the Software Market", attempted to apply the theory of market leaders and endogenous market structures to the analysis of an important market of the New Economythe software market. The author focused on the New Economy, which was developed in the last decades around the personal computer industry and the Internet. First of all, while traditional sectors are often characterized by competition in the market with substantial product differentiation and U-shaped cost functions, many markets of the New Economy are often driven by competition for the market taking place through high fixed costs of investment in R&D, and production is typically characterized by small and constant marginal costs. These strong differences require a new approach to the analysis of markets and of the behavior of their leaders.

Fangcheng Tang, Weizhou Zhong and Shunfeng Song in the paper, "Tendering with Different Risk Preferences", theoretically developed a general tender model to examine the tenderers' behaviors in one-shot construction bid auctions. This model generalizes competitive sealed-bid auction theories by allowing different risk preferences and predicts price quoting behaviors of different tenderers in the tendering process. The model theoretically proves that a tenderer's bid is affected by his risk preference. Specifically, in a lowest-price sealed-bid process, risk-averse tenderers tend to quote a higher price, risk-seeking tenderers a lower price, and risk-neutral tenderers an average price. In view of this, the authors point out that risk-seeking tenderers are more likely to win the contracts.

M Upender and M Sujan in the paper, "Cointegration Between Labor Productivity and Wage Rates: Empirical Evidence from the Indian Industries", examined the cointegration between labor productivity and money wage rates in the Indian industries (factory sector) during 1980-81 to 2004-05. The empirical results based on unit root tests and cointegration modeling illustrate that, though the labor productivity and money wage rate series are nonstationary in log level form, their linear combination is stationary in level form evincing the fact that labor productivity and money wage rate in the Indian industries are cointegrated in the long run. As the substitution possibilities of labor for capital are more in the Indian industries in the long run, the policy decisions to enhance the money wage rate by 1% would improve the labor productivity, on average, by more than 1% in the Indian industries, other things remaining constant.

S S Rajan, K L N Reddy and V Pandit in the paper, "Total Factor Productivity in Selected Indian Manufacturing Industries", examined productivity growth for the two sub-periods, i.e., pre-reform (1973-74 to 1992-93) and post-reform (1993-94 to 2004-05), for possible structural changes due to policy reforms. They observed that so far as iron and steel industry is concerned productivity growth has declined in the second sub-period (post-reform period). Technological progress during the nineties has significantly slackened though it remains positive. On the other hand, aluminum and refined petroleum industries have maintained consistency in their productivity growth without much volatility. They pointed out that the productivity in refined petroleum products has continued to rise consistently in spite of two big oil crises and increasing cost of crude oil. Labor productivity for all the three industries shows a positive and significant trend.

- M Aruna
Consulting Editor