COST BEHAVIOR AS A PARAMETER OF PRODUCTIVE EFFICIENCY: AN EMPIRICAL ANALYSIS OF THE COMPANHIA VALE DO RIO DOCE BEFORE AND AFTER PRIVATIZATION

Abstract

With the reduction of state participation in the economy, the search to collect evidence about the effects of privatization on the development of companies has grown more and more. Therefore, the objective of this paper is to test the hypothesis of improvement in the productive efficiency of the company Companhia Vale do Rio Doce, privatized in 1997, starting with empirical identification of the company’s production costs. Separation of costs into their fixed components and variables component was accomplished through simple linear regression between the variables cost of goods sold and operating profit, taken from the accounting statements published between the years 1990 to 2004. To achieve the objective, a modification of the original concept of primary costs was considered which now represents only direct materials, in order to meet the demands of Brazilian labor law. Association among the identified variables was tested through the correlation coefficient (r), the determination coefficient (r2) and the t-test statistics. The parametric test of equality of averages of the primary costs was then applied to the previous and subsequent sets of time of the privatization, seeking to achieve the objectives of the study. The obtained result corroborates the hypothesis of this research, i.e., the period subsequent to the event presents significant improvement of the productive efficiency of the company compared to the period prior to the event. Keywords: Primary costs. Regression analysis. Test of averages. Privatization.