The Intergenerational Supply of Loggers Under Conditions of Declining Economic Well-Being

This paper addresses the supply-side explanations of a logger shortage by estimating an occupational choice model that considers the role of earnings, nonpecuniary determinants and intergenerational factors. Our results showed that: (1) relative earnings have no statistically significant effect on career choice; (2) improvement in the public image of loggers substantially increases entry into logging; and (3) a strong intergenerational supply linkage exists but is currently being eroded.     

GOVERNMENT POLICIES AND AGRICULTURAL SUPPLY RESPONSE: PADDY IN SRI LANKA

An aggregate analysis of supply response in the paddy (rice) sector of Sri Lanka during 1952-87 is conducted to identify the impact of pricing policy, irrigation programmes, institutional credit and concessional sales on area, yield and overall supply. The focus of the estimation procedure is the selection of an appropriate functional form for regressions and on the price variable that best represents the price to which producers respond in making area and yield decisions. In the case of both area and yield, the econometric criteria favour the acceptance of log-linear equations with the ratio of the guaranteed price of paddy to fertiliser price. On the basis of overall supply elasticity estimates, it is concluded that while pricing policy, irrigation programmes and institutional credit provide incentives to the expansion of paddy production, concessional sales of rice act as a disincentive.     

Polynomial approximations in cross-sectional models

The time-series distributed lag techniques of econometrics can be usefully applied to cross-sectional, spatial and cross-section time-series situations. The application is perfectly natural in cross-section, time-series models when regression coefficients evolve systematically as the cross-section grouping variable changes. The evolution of such coefficients lends itself to polynomial approximation or more general smoothing restrictions. These ideas are not new, Gersovitz and McKinnon (1978) and Trivedi and Lee (1981) providing two of the earliest applications of cross-equation smoothing techniques. However, their applications were in the context of coefficient variation due to seasonal changes and this may account for the non-diffusion of these techniques. The approach here is illustrated in the context of age-specific household formation equations based on census data, using Almon polynomials when the regression coefficients vary systematically by age group. A second application is provided, using spatial data, explaining the incidence of crime, by region; using polynomial and geometric smoothing to model distance declining regional effects.     

On the E-optimality of truncated block designs

Sufficient conditions are found for designs, derived from completely symmetric designs by deleting binary blocks, to be E-optimal. Sufficient conditions are also found for E-optimality of designs obtained from other E-optimal designs by deleting all blocks forming a balanced incomplete block design on a subset of the treatments. The results include many binary and non-binary designs for which E-optimality was previously unknown.