The effect of within-person variance on prevalence estimates from population distributions based on a single measurement was examined for hematologic and iron-status indicators collected in the Hispanic Health and Nutrition Examination Survey (HHANES). Within-person to between-person variance ratios (W:Bs) were estimated for 11 indicators by using data from 80 persons who provided blood twice in HHANES. Distributions of selected iron-status indicators from 20-44-y-old Mexican American females from HHANES were adjusted for within-person variance by using the W:B estimates, and prevalences of low values based on the original and adjusted distributions were compared. W:B were < 1 for the majority of the indicators. Nonetheless, prevalences of low values from the original distributions were inflated when commonly used cutoff values were applied. Within-person variance in serum analytes needs to be controlled when the prevalence of a condition in populations is assessed.

In field experiments, based on sensitivity (as indicated by the range in tissue concentrations in response to variations in N supply) and on the correlations between nitrate-N and total-N concentrations and percent relative marketable yield, it was found that nitrate-N and total-N concentrations in youngest fully expanded blades (YFEB) were suitable indicators of the N status of onion plants. Based on the variation in critical values between sites (reproducibility), total-N is preferred to nitrate-N. Correlations between nitrate-N and total-N concentrations in YFEB and bulb quality attributes (scale thickness, glucose concentration, fructose concentration, soluble solids and dry matter) were poor and of little predictive value.

This paper discusses the costs and returns of three phases in milkfish culture as practiced in the Philippines namely: nursery; stunting or retarding the growth of milkfish fingerlings; and modular culture system. The economic indicators used are average rate of return or return on investment and payback period. The economic analysis was based on experiments undertaken at the Leganes Research Station of SEAFDEC Aquaculture Department and verified in three sites located in the provinces of Negros Occidental (2 sites) and Cebu (1 site).

This paper catalogs the business cycle properties of 163 monthly U.S. economic time series over the three decades from 1959 through 1988. Two general sets of summary statistics are reported. The first set measures the comovement of each individual time series with a reference series representing real economic activity. These statistics focus on comovements at business cycle horizons. The second set of statistics examines the predictive content of each of the series for aggregate activity, relative to different sets of conditioning (or predictive) variables. These statistics are constructed and presented in a way that facilitates comparisons across series and across conditioning sets. They also provide new lists of leading indicators based on predictive content for overall economic activity. Some of the results confirm previously recognized empirical regularities, while others provide new or different insights into the business cycle properties of various series.

A model of policy making is developed where governments seek to maximize support from social groups through the combination of both PERT (social‐welfare‐increasing) and PERT (welfare‐transferring) policies. The implicit weights of a political preference function shift with a change in the relative cost of interest group organizing. Attention is paid to the degree of wealth transfers as total social welfare increases because of PERT policy changes. The model demonstrates that, in the case of two competing groups, the weight given to one group in the allocation of social surplus will increase as total social welfare increases with a bias toward the other group. The relative weights placed on consumers and producers based on PEST policies alone are misleading indicators of the political influence of groups. A number of general implications of this political economic analysis for the reform of public policies are investigated.

A model of policy making is developed where governments seek to maximize support from social groups through the combination of both PERT (social-welfare-increasing) and PERT (welfare-transferring) policies. The implicit weights of a political preference function shift with a change in the relative cost of interest group organizing. Attention is paid to the degree of wealth transfers as total social welfare increases because of PERT policy changes. The model demonstrates that, in the case of two competing groups, the weight given to one group in the allocation of social surplus will increase as total social welfare increases with a bias toward the other group. The relative weights placed on consumers and producers based on PEST policies alone are misleading indicators of the political influence of groups. A number of general implications of this political economic analysis for the reform of public policies are investigated.

The accuracy of body mass indices (BMIs), such as Quetelet's index, for the definition of obesity was investigated in a large sample of healthy humans. Two hundred thirteen women and 150 men with a wide spectrum of weights, heights, and ages underwent densitometric analysis for the determination of percent body fat (%BF). %BF was then contrasted with various well-established BMIs. Although %BF was correlated with all the BMIs (r = 0.60-0.82), applying objective definitions of obesity based on BMIs or %BF by densitometry often produced conflicting results. It was also found that the 95% confidence intervals for predicting %BF by using Quetelet's index were very wide. Because of the wide variation for individuals between densitometrically determined body fat and body fat as estimated by BMIs, we conclude that BMIs should be used with caution as indicators of obesity.

This country strategy for 1992-1993 was prepared based on instructions from IICA headquarters, and shows in general and specific terms the interest from the government, non-goverment organizations, private sector and farmers in Suriname. It also shows the areas in which IICA technical cooperation is needed to ameliorate and solve partially, some of the many problems of the agricultural sector. The table of contents includes: 1) overall economic situation of the country, employment, generation of foreign income, per capita income, problems that limit agricultural and rural development, among others; 2) an introduction with three interviews: international organizations, government level and private sector; 3) summary of the sectoral assessment: development strategy of the country, main characteristics and performance of the economy, performance of the principal economic indicators and agricultural sector; 4) components of the strategy: definition of priority areas for IICA cooperation, identification of cooperation instruments to be used, mechanisms for reaching agreement and for consultation, and resource needs. Appendicies. (MIBA)

This country strategy for 1992-1993 was prepared based on instructions from IICA headquarters, and shows in general and specific terms the interest from the government, non-goverment organizations, private sector and farmers in Suriname. It also shows the areas in which IICA technical cooperation is needed to ameliorate and solve partially, some of the many problems of the agricultural sector. The table of contents includes: 1) overall economic situation of the country, employment, generation of foreign income, per capita income, problems that limit agricultural and rural development, among others; 2) an introduction with three interviews: international organizations, government level and private sector; 3) summary of the sectoral assessment: development strategy of the country, main characteristics and performance of the economy, performance of the principal economic indicators and agricultural sector; 4) components of the strategy: definition of priority areas for IICA cooperation, identification of cooperation instruments to be used, mechanisms for reaching agreement and for consultation, and resource needs. Appendicies.

Effects of decreasing water application on water stress indicators of high frequency drip-irrigated processing tomatoes was studied at the Water Management Research Laboratory in Fresno, California. Irrigation treatments were arranged in a randomized block design to produce five levels of water stress: T1= 0.40 ETc; T2= 0.60 ETc; T3== 0.80 ETc; T4= 1.0 ETc; T5= 1.20 ETc. The irrigation for each treatment was controlled automatically by a desktop computer using the electronic fluid level sensor wich measured evaporation of water Class "A" evaporation pan. Several soil and plant parameters were systematically monitored either manualy or by computer. Results from this experiment indicate that (1) soil matric potentials sensors (SMPS) could be used to schedule and control irrigation. Simultaneous measurents avoid poor decisions based on a typical conditions. (2) Crop Water stress index method (CWSI) appears to be usefull to schedule/control irrigation or characterize water stress in tomato plants. A considerable variability was determined in this method. (3) Some statistical significant correlations were found between stem diameter changes and leaf water potential. Water applied, yield and tomato quality are also presented.