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Sex differences in three communication behaviors consistently found to be more common among females than males — smiling, gazing at one's partner, and sentence complexity — were examined through analysis of interviews with 78 institutionalized mentally retarded adults. While females were significantly more likely than males to smile or laugh, and tended to use longer, more complex sentences, the commonly observed sex difference in gazing failed to generalize to a retarded sample. These findings clarify limits on the generalizability of sex differences beyond college students and other normal populations.This research was partially supported by a grant to the Texas Tech University Research and Training Center in Mental Retardation from the Rehabilitation Services Administration, Department of Health Education, and Welfare.  相似文献   
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S. K. Gaisie 《Demography》1975,12(1):21-34
This paper attempts to measure infant and child mortality levels and also to determine their structure by utilizing the results of the 1968–1969 National Demographic Sample Survey which was conducted under the directorship of the author. Among the major problems encountered in the exercise are the adjustment of the current raw mortality data and the estimation of infant and child mortality from independent source material. The estimated infant mortality rates range from 56 per 1,000 live births in the Accra Capital District to 192 in the Upper Region during the late 1960’s. The urban rate is lower than the rural rate, 98 as against 161 per 1,000 live births. A large proportion of the deaths among children aged 0–4 occur in the second year of life, and deaths in this age group account for the bulk of the deaths within the age group 1–4 years.  相似文献   
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In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.  相似文献   
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Previous research shows that living in a non-intact family is associated with educational disadvantages. This paper compares the relationships between childhood family structure, schooling, and earnings in Sweden and the USA. This comparison is interesting because both family structure and public policies differ significantly. We find a negative relationship between living in a non-intact family and child outcomes, and the estimates are remarkably similar in both countries. After using sibling-difference models, the correlation with family structure is no longer significant. These results cast doubt on the causal interpretation of the negative relationship between non-intact family structures and child outcomes.  相似文献   
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