A note on the efficiencies of two almost unbiased predictive ratio estimators

Using the predictive approach advocated by Basu (1971), we consider two almost unbiased ratio estimators of the population mean and study their efficiencies under a linear model.     

Efficiencies of six almost unbiased ratio estimators under a particular model

Efficiencies of six almost unbiased estimators for the ratio of population means of two characters, are compared under a linear regression model.     

Spacing Between Births in Odisha,India

Birth spacing is of considerable importance to study the tempo and quantum of fertility. Using data from the National Family Health Survey III, this study explored the birth interval dynamics in Odisha, an eastern state of India. The life table analysis of spacing between births clearly suggests that birth spacing in the recent past has increased and the proportion of women moving to the second, third, and fourth parity has declined, leading to the decline in fertility in Odisha. From the proportional hazards model, educational level of women, age of women at previous birth, sex and survival status of the previous child, and the period effect are found to be important determinants of birth spacing at higher parities. Socioeconomic differences do not show a large effect at lower order births. This highlights the fact that most women in Odisha, regardless of their background characteristics, tend to have second births.     

Non-parametric measurement of economies of scale and scope in non-competitive environment with price uncertainty

In non-competitive market characterized by heterogeneous firms and price uncertainty, we discuss the measurement of economies of scale and scope due to process indivisibilities arising from the task-specific production processes of multiproduct firm. Two competing DEA cost models—one based on the factor-based technology set and the other based on cost-based technology set, are examined in terms of their relative strengths and weakness to reveal scale and scope economies. Given the assumptions underlying both cost models, it is argued that the latter model may be relatively flexible and empirically demanding over the former one. The flexibilities are described in terms of price uncertainty; firms' heterogeneity; and the control over on the mix and quantities of inputs and their prices. And, as regards the underlying linkage of scale with scope properties with respect to diversified vis-à-vis additive firm, we find that the former model not only fails to exhibit one important property, i.e., the independence between scope properties of diversified firm and scale properties of additive firm, but also reveals one strange property, i.e., falling of scale elasticity of an additive firm irrespective of its no economies or diseconomies of scale possibility.     

Empirical comparison of some regression and regression-type strategies

The main advantages of the regression estimator are that it can be used for both the situations of positively and negatively correlated variables and its precision is usually higher than the simple expansion (direct), ratio and product estimators. Extensive empirical studies on the properties of many types of ratio estimators have been undertaken in several papers, for example by Rao (1969), Rao and Rao (1971), Hutchinson (1971), Royall and Cumberland (1981), Wu and Deng (1983). However not much attention has been given to the use of similar methods for regression-type estimators. In this paper, an attempt has been made to compare the relative performances of some biased and unbiased regression-type strategies with the help of a wide variety of natural populations.     

From ‘temporary migrants’ to ‘permanent residents’: Indian H-1B visa holders in the United States

Literature on international migration from India in the past has focused on the formation and development of ‘Indian diasporas’; that is, Indians who have moved to various parts of the world and maintain socio-economic, cultural and political lives in India as well as other countries. However, little attention has been paid toward ‘temporary migrants’ who have migrated to different countries with a temporary visa and in the course of time extended their visas to become ‘permanent residents’. Temporary migration from India has become a common trend over the last two decades, especially since the acceleration of globalisation and the developments in the fields of information and communication technologies. Although it is argued that this type of migration took place in the past – for instance, Indians migrated to British, French, Dutch and Portuguese colonies during the nineteenth and early part of the twentieth centuries as indentured labourers for a period of three to five years and later extended their stays – what is new about the current trend is the new state policies of different host countries and the socio-economic and cultural background of the immigrants. This paper is an exploratory study of this contemporary phenomena of movement from ‘temporary migrant’ to ‘permanent resident’, a phenomena which has not been given much attention by academicians and policy makers in India. The present paper outlines this trend with an illustration of Indian H-1B visa holders in the United States.     

Seasonal migration of rural labor in India

The impact of seasonal migration has been overlooked by students of migration. A unique data set collected in Dungarpur – one of the less developed districts of India – allows us to closely examine both the determinants and impact of seasonal migration. Detailed information was gathered from all members of 624 households, thus enabling analyses at both individual and household levels. The findings indicate that seasonal migration among rural laborers is wide-spread. Rural households in India use migrant labor offered by their members to improve their well-being by both reducing the impacts of inferior conditions and by raising household's income levels. Migrant labor is a compensating mechanism used by households to reduce their disadvantageous position. Migrant households are characterized by lower education levels, lower levels of income from agriculture, and by an inferior geographical location. However, those households sending migrant labor are found to have higher income levels than those not sending migrant labor. Income from migrant labor accounts for almost 60% of total annual income of households sending at least one migrant laborer. Such findings are in accordance with explanations derived from the `new economics of migration'. We can thus learn that migration-related decisions should not evaluated only on the basis of utility maximization of individual migrants, but also on the basis of risk reducing by households.     

A note on an IPPS sampling scheme

Summary This paper presents a new IPPS sampling scheme possessing some desirable properties and providing an unbiased and non-negative variance estimator under H-T model. An empirical study is also undertaken to examine the performance of the scheme compared to some standard sampling schemes. The authors are grateful to the referees for providing many helpful suggestions on the earlier draft of the paper.     

A Class of Estimators Using Auxiliary Information in Two-Stage Sampling

This paper presents a general class of estimators for the finite population total when the emphasis is laid on the use of two auxiliary variables in a two-stage sampling.