ESTIMATING TEMPORAL FARM INCOME DISTRIBUTIONS USING SPATIAL SMOOTHING TECHNIQUES

The Australian Bureau of Agricultural & Resource Economics (ABARE) has conducted the annual Australian Agricultural and Grazing Industries Survey, covering the broadacre sector, in a consistent format since 1978/79. In this period the incomes of farmers have fluctuated considerably. Interest has focused on temporal income variation because of its relationship to the inherent riskiness of farming. Part of these income fluctuations can be explained by changing commodity prices and by highly variable climatic conditions. This paper outlines a method of measuring the magnitude of this income variation and how it relates to other variables. Due to rotation within the sample of farms surveyed, data are limited for determining the income variability of any particular farm. This paper, using spatial locations of surveyed farms, shows how kernel smoothing techniques can be adapted to estimate the distribution of a farm's income. This analysis uses data collected from 1978/79 to 1991/92. Summary information from these distributions is cross-tabulated against several other variables. This shows that income variability is strongly related to the production mixture of farming businesses.     

A BERRY-ESSEEN BOUND FOR THE RATIO ESTIMATOR

Suppose that R is the ratio estimator based on a simple random sample of size n drawn without replacement from a bivariate population of N elements. A Berry-Esseen bound for von Mises statistics based on samples from a finite population is used to derive a Berry-Esseen bound for R.     

A Comparision of Two Methods of Linking Spatial and Economic Data from Farm Surveys

Linking scientific and economic data potentially has many benefits for natural resource management and policy analysis. This paper compares a sophisticated method for bringing these data together in farm surveys using detailed farm boundary data collected during an interview, with a less onerous approach requiring only a single point from each surveyed farm. A comparison is made by modelling land values using regression analysis in central New South Wales. It was found that there were only minor additional benefits from using the more sophisticated approach in this case. Additionally, there are significant costs in collecting and processing the detailed georeferencing data that make it considerably less practical than the simpler approach.     

Combination of a structured aerobic and resistance exercise improves glycaemic control in pregnant women diagnosed with gestational diabetes mellitus. A randomised controlled trial

Problem

Gestational diabetes mellitus, defined as any carbohydrate intolerance first diagnosed during pregnancy, is associated with a variety of adverse outcomes, both for the mother and her child.

On Tests of Uniformity for Randomly Distributed Arcs on a Circle

Let n points be independently distributed on a circle. Moving in a counter-clockwise direction, place arcs of length a on the circle with the i^th are starting at the i^th point. We describe three simple tests of the hypothesis of uniformity based on vacancy, on number of spacings and on the length of the maximal spacing. The tests do not require knowledge of the random points. The asymptotic power of these tests is investigated, and it is shown that vacancy-based tests perform best of the three.