A SIMPLE TEST FOR UNIFORMITY

Abstract A new and very simple test for uniformity is proposed. An exact formula for the distribution under H₀ of the corresponding test statistic is derived. This formula is only suitable for computer-oriented use. For other circumstances a table of critical values is given. The power of the test is compared with that of two well-known alternatives: the χ²-test and the Kolmogorov-Smirnov test.     

PRIVATIZATION AND EFFICIENCY: FROM PRINCIPALS AND AGENTS TO POLITICAL ECONOMY

Abstract.  We survey the theoretical literature on privatization and efficiency by tracing its evolution from the applications of agency theory to recent contributions in the field of political economy. The former extend the theory of regulation with incomplete information to address privatization issues, comparing state-owned enterprises with private regulated firms. The benefits of privatization may derive either from the constraints it places on malevolent agents or from the impossibility of commitment by a benevolent government because of incomplete contracts. Contributions dealing with political economy issues separate privatization from restructuring decisions. They either explore bargaining between managers and politicians or analyse the impact of privatization shaped by political preferences on efficiency. The theoretical results regarding the relation between privatization and efficiency do not lead to any definitive conclusion. Privatization may increase productive efficiency when restructuring takes place whereas its effects on allocative efficiency still remain uncertain.     

A GENERALIZED SIGNED–RANK TEST FOR COMPARISON OF P TREATMENTS

Abstract. Several generalizations of the signed–rank test for testing of equality of p treatments in p related samples against general and trend alternative are discussed. A new generalized test is described and exemplified.     

THE RELATIONSHIP BETWEEN RELATIVE RISK AVERSION AND THE LEVEL OF EDUCATION: A SURVEY AND IMPLICATIONS FOR THE DEMAND FOR LIFE INSURANCE

The expected utility hypothesis has been widely used in the construction of economic models and numerous difficulties are encountered in attempting to take into account preferences toward risk in a real‐world setting. More recently, attention has focused on comparative studies in economics and business in an international framework and problems related to the hypothesis of relative risk aversion (RRA). One ambiguous hypothesis is the relationship between the level of RRA and the level of education, which has been found either positive or negative. From a causality point of view, it may be argued that investors with a high level of education are less risk averse, but it may also be argued that less risk‐averse individuals choose to pursue a higher level of education. The purpose of this paper is to survey the empirical literature on this subject. It provides evidence that risk aversion is negatively correlated with higher education and human development. The results have important implications for macroeconomic empirical studies and the demand for financial assets and more specifically on the demand for life insurance. Assuming the same degree of RRA for utility‐maximizing consumers should be limited to homogeneous samples.     

PERFORMANCE OF MURPHY'S TEST FOR TWO OUTLIERS IN A LINEAR MODEL

Abstract. In JOSHI and LALITHA (1986) a test for two outliers in the same direction in a linear model is discussed. Here the performance of this statistic is studied. For this, the exact non–null density function of the random variables involved in defining the statistic is obtained. Then a measure of performance is defined and it is applied to the case of a random sample from a normal distribution, as in this case the above said statistic reduces to the well known Murphy's test statistic. These values are then compared with the power values obtained by HAWKINS (1978).     

On the Use and Utility of the Reliability Coefficient in Social and Behavioral Research

This note discusses the use and utility of the reliability concept in social and behavioral research. The focus is on the meaning and limitations of the classical test theory reliability coefficient. Conditions are examined under which reliability is a meaningful notion, and the amount of information it can provide then. Issues pertaining to limitations of the practice of social and behavioral measurement and its implications for indices of measurement accuracy are subsequently discussed.     

Identifying Optimal Items in Quality of Life Assessment

Quality of life has drawn increasing attention in health science and more efforts have been devoted to develop instruments that are valid and reliable to assess quality of life. The World Health Organization (WHO) has devised an instrument World Health Organization Quality of Life Survey- Abbreviated Version (WHOQOL-BREF) to assess quality of life, but the psychometric property of each individual item has not been studied yet. Using item response theory, we examine the properties of the WHOQOL-BRIEF Taiwan version. Samejima’s graded response model was fitted, and item parameters were calculated. The items were ranked base on their discrimination power, and the best items are identified. Several data with subset of items (22, 20, 18, 16 and 14 items) were created by omitting items with lower discrimination power. The test information function of the full questionnaire and the subsets were compared. The results showed there were significant positive correlations between the full questionnaire and the subsets of items and the distributions are similar. The test information function showed the maximum amount of test information spaced over two ends of the theta continuum, and this suggested that the WHOQOL-BREF provided more information for groups with either lower or higher satisfaction of quality of life, while it is less discriminating for individuals in the middle range.     

A COMPARISON OF THE POWERS OF A GENERALIZED FRIEDMAN'S RANK TEST AND AN ALIGNED RANK PROCEDURE BASED ON SIMULATION

This paper presents the results of an experimental determination by Monte Carlo techniques of the power functions of a generalized Friedman's rank test based on "standardized" ranks and a proposed test procedure based on aligned ranks for orthogonal designs. The simulation is carried out for five orthogonal designs and a number of Normal location alternatives and gives some information about the difference in power of the two test procedures for some orthogonal designs.