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Abstract: This study presents an adaptive intelligent algorithm for forecasting gasoline demand based of artificial neural network (ANN), conventional regression and design of experiment (DOE). To show the superiority and applicability of the proposed algorithm it has been applied for monthly demand estimation of gasoline in Japan, USA, Kuwait, Canada and Iran within 1992–2005. The economic indicators used in this paper are price, GDP (Gross Domestic Production), population, number of vehicles, gasoline demand in the last periods and correlation coefficient between variables. The proposed algorithm may be used to estimate gasoline demand in the future by optimizing parameter values. The proposed algorithm uses ANOVA to select either ANN or regression for future demand estimation. Furthermore, if the null hypothesis in ANOVA and F-test is rejected, the Duncan method is used to identify which model is closer to actual data at α level of significance. Neural network is an intelligent, adaptive and optimizing method for solving the complicated problems. The results show that ANN provides far less error than regression. Moreover, the proposed algorithm provides near optimal solution for gasoline demand estimation due to its flexibility and intelligibility. The intelligent algorithm is therefore ideal for policy making with respect to gasoline consumption estimation. [ABSTRACT FROM AUTHOR]

Abstract: Objective To examine the adequacy of dietary intake of calcium; folate; and vitamins C, D, E, B-6, and B-12 in premenopausal US women of differing ethnicity. Design Analyses of single and duplicate 24-hour recalls were conducted to determine dietary intake during the Third National Health and Nutrition Examination Survey. Subjects Three thousand five hundred eighty-five randomly selected women aged 20 to 50 years from across the United States who were not pregnant or lactating were examined between 1988 and 1994. Statistical analyses Usual nutrient intake distributions were estimated using the Iowa State University method for adjustment of the distribution. The Estimated Average Requirement cut-point method was used to determine the proportion of women with inadequate intake for each nutrient in each ethnic group. Results More than 75% of women irrespective of ethnic group had usual intakes of calcium lower than the new Adequate Intake. More than 90% of the women had inadequate intakes of folate and vitamin E from food sources alone. More than half of smokers had inadequate intakes of vitamin C. Intakes of vitamins B-6 and B-12 were low in less than 10% of these women. Applications/Conclusions This article provides evidence that a high proportion of premenopausal US women are underconsuming a variety of nutrients. Dietary intakes alone are not currently adequate to meet the new recommended intakes. Nutritional supplement use is widespread and effective, but does not eliminate the concerns for at-risk populations. Awareness of the general inadequacies in intakes of vitamin E and folic acid at large, and in many women vitamin C as well, can help direct individual dietary recommendations and place the emphasis in group counseling on nutrients that are of widespread concern. In addition, foods rich in vitamins B-6 and of general nutritional benefit should be emphasized among African American women in the United States as a substantial proportion of this group is still showing inadequate intakes from foods. J Am Diet Assoc. 2003;103:1008-1014. [Copyright &y& Elsevier]

Within- and between-person variation in nutrient intake has been characterized in different adult populations, but little is known of country, age, or sex differences among children. The objectives of this study were as follows: 1) to describe the mean intake, within- and between-individual CV and variance ratios of nutrient intake among children ages 9-18 y old in Russia and the United States in 1996; 2) to compare the age and sex-related differences in nutrient intake variance within and between countries; and 3) to hypothesize about the feasibility of using within-individual variance estimates from one nationally representative sample to adjust the usual intake distributions in another nationally representative sample. Mean intakes of all nutrients except magnesium were significantly higher among U.S. children (P < 0.001); within-person variation was higher among the U.S. children, possibly indicating greater access to a wide array of foods. Strong differentials existed in variance components by sex in both countries, although not in the same direction, and differed by age in U.S. girls. Ratios of within- to between-person variance in 8 of 11 nutrients were lower among Russian (range: 0.9-1.6) than U.S. children (range: 1.4-1.7), suggesting that day-to-day bias may not affect Russian dietary recalls as strongly as in the United States. Researchers are encouraged to use these estimates to conduct sensitivity analyses of usual intake distributions in their own data when multiple days of data collection are not feasible. [ABSTRACT FROM AUTHOR]