Lactation and fertility in Rural Bangladesh

Summary Analysis of data from various phases of a study of post-partum amenorrhoea in Bangladesh illustrated good aggregate consistency of response on menstrual status, but less individual consistency on duration of post-partum amenorrhoea. Using life table techniques, the median duration of amenorrhoea was calculated as 19.9 months for women with births between February and September 1974. There were substantial seasonal variations in duration, with the median decreasing from 21.5 months for women with February births to 16.9 months for those with September births. By contrast, the median duration of post-partum amenorrhoea varies by only two months for women in the lowest and highest quartiles of weight and weight for height. The seasonal pattern was similar for all weight groups.     

Binge drinking and labor market success: a longitudinal study on young people

This paper presents a two-equation model of joint outcomes on an individual’s decision to binge drink and on his/her annual labor market earnings. The primary data source is the 1979 cohort of the National Longitudinal Survey of Youth (NLSY79), 1979–1994. We show that binge drinking behavior is quite alcohol-price responsive and is a rational addiction. A new result is that an individual’s decision to binge drink has a statistically significant negative effect on his/her earnings. Furthermore, we conducted simulations of the short-run and long-run impacts of increasing the alcohol price. They showed that the tendency for an individual to binge drink heavily is reduced significantly, and the reduction is greater in the long-run than short-run simulation. Also, an individual's annual earnings were increased. However, in the structural model, an individual’s earnings have no significant effect on his/her tendency to engage in binge drinking. Our results contradict earlier findings from cross-section evidence that showed increased alcohol consumption raised an individual’s earnings or wages.     

Food Assistance Programs and Outcomes in the Context of Welfare Reform*

Objective. Food assistance programs play an important role in meeting the basic needs of low‐income households. We consider how the Food Stamp Program (FSP), labor force participation, and food insecurity status affect outcomes of low‐income households under different program designs and economic conditions. Methods. Data from the Survey of Program Dynamics allow estimation of the effects of participation in FSP, labor market participation, and food insecurity on each other. To obtain estimates of behavioral relationships, we apply a simultaneous equation model and make a set of plausible assumptions about identification to implement the instrumental variable estimation. Results. Food insecurity has a positive effect on FSP participation, while labor force participation reduces FSP participation. Furthermore, FSP participation is more responsive to changes in the amount of program benefits than to changes in nonlabor income. Labor force participation has no direct effect on food insecurity; although not statistically significant, the effect of FSP participation on food insecurity is positive. A higher wage rate decreases FSP participation and increases participation in the labor force. Conclusion. The structural approach, which relies on particular identifying assumptions, allows us to explicity examine linkages among food program participation, labor force participation, and well‐being, measured in terms of food insecurity. The results provide evidence that among low‐income households, program parameters affect FSP participation, but no evidence that the food assistance reduces food insecurity.     

Birth-interval dynamics in rural Bangladesh and maternal weight

This article reports on the results of a study conducted in rural Bangladesh on the influence of maternal weight on the components of birth intervals, including gestation and intrauterine mortality, the duration of postpartum amenorrhea, and the duration of waiting time to conception (the menstrual interval). When biological factors (including maternal age, parity, and supplementation practices) and behavioral variables, including religion, education, and occupation, were controlled, maternal weight was found to be related to the risk of intrauterine mortality and to the probability of resuming menses in the postpartum period. The implications of these findings for policies and programs in developing countries are discussed.     

Nutrition and Fertility in Bangladesh: Breastfeeding and Post Partum Amenorrhoea

From 1975 to 1980 a prospective study a nearly 2,500 married, fertile women was conducted in Matlab, Bangladesh at the International Centre for Diarrhoeal Disease Research. Women were interviewed at monthly intervals to collect information on nutritional and reproductive status, in order to study the factors associated with natural fertility. The median duration of amenorrhoea for women with no child deaths was 15.5 months, with older women and those of higher parities recording longer durations than younger women or those of lower parities. Median duration of amenorrhoea for women with six or more years of education was 8.4 months compared to 16.4 months among women with no education. When classified by weight at pregnancy termination, average duration of amenorrhoea of women weighing less than 38 kg was 17.6 months compared to 13.6 months among women weighing more than 44 kg. Proportional hazards analyses show that mother's education, parity, month of birth, supplementation practices and nutritional status were significantly associated with the probability of resuming menstruation.     

The Effects of Modeling and Experience on Young Children's Persistence at a Gambling Game

Gambling is common among children and adolescents, but Hide is known about factors initiating or maintaining this behavior. Fifty-one male and 51 female kindergarten and first grade children were invited to play a game involving repeated opportunities to select colored chips from a cup while blindfolded. Children playing for tangible incentives elected to play longer than those who were not (p < .001). Seeing a videotaped model win or fail to win a large prize had no effect on persistence with the game. Playing again one week later, children playing for incentives exhibited a more successful strategy, quitting sooner (p < .04) and with more winnings (p < .03). The parameters of experiential versus observational learning are discussed, with implications for educating children about risk-taking.     

Attitudinal Polarization and Trimodal Distributions: Measurement Problems and Theoretical Implications

Objective . We present trimodality as a distributional pattern that is relevant to conceptual issues of attitudinal polarization but fits nowhere along the modality-bimodality continuum. Methods . We use simulated univariate distributions and distributions taken from the 1994 General Social Survey to investigate how commonly used measures track (or fail to track) noteworthy shifts in the distributions. Results . The kurtosis and variance are largely insensitive to important distributional differences, most importantly that between bimodality and trimodality. Conclusions . We argue that the lack of attention to trimodality and the insensitivity of commonly used measures of polarization (kurtosis in particular) to that distributional pattern create a blind spot in our thinking about polarization and can lead to basic misinterpretations of extant patterns in public opinion data.     

Comparing two poisson parameters: what to do when the optimal isn't done

Suppose two Poisson processes with rates γ₁ and γ₂ are observed for fixed times t_l and t₂. This paper considers hypothesis tests and confidence intervals for the parameter ρ = γ₂/γ₁. Uniformly most powerful unbiased tests and uniformly most accurate unbiased confidence intervals exist for ρ, but they require randomization and so are not used in practice. Several alternative procedures have been proposed. In the context of one-sided hypothesis tests these procedures are reviewed and compared on numerical grounds and by use of the conditionality and repeated sampling principles. It is argued that a conditional binomial test which rejects with conditional level closest to but not necessarily less than, the nominal a is the most reasonable. This test is different from the usual conditional binomial test which rejects with conditional level closeset to but less than or equal to the nominal α Numerical results indicate that an approximate procedure based on the Poisson variance stabilizing transformation has properties similar to the preferred conditional binomial test. Values for λ₁ = t₁λ₁ required to achieve a specified power are considered. These results are also discussed in terms of test inversion to obtain confidence intervals.