Statistic problems regarding tuberculosis infection and morbidity of tuberculosis

The statistic relations between tubercular infection and morbidity are comparatively complicated, partly because the infection rate will depend on age and calendar time, partly because of the varying interval (latent period) which may pass from the time of infection to the disease. A theoretical analysis of these relations may possibly count on a certain amount of interest to future statistic investigations regarding tuberculosis. It is my opinion that too little attention lias been paid to them in many of the investigations which have hitherto been carried out.     

Spatial aspects of the diffusion of technological innovations among American municipal governments

Examination of the spatial diffusion patterns of a sample of 43 technological innovations organized into four functional areas—fire fighting, traffic control, air pollution control, solid waste collection, and disposal—indicates the absence of systematic patterns of either rank-size or contagious diffusion of these innovations among municipal governments in the United States. Absence of these general patterns reflects an inadequate identification in existing theories of spatial diffusion processes of variables that enter into agency decisions to adopt new technologies and the inadequate identification of possible interactions among variables. In particular, attempts to model diffusion patterns based on neighborhood effect or on hierarchical relationships fail to take into account, it least for the classes of adopters and innovations studied here, polynuclear propagation and the role of intermediaries (e.g. professional associations, governmental agencies, suppliers) in communication patterns or the role of site-specific factors that determine the “suitability” or “worth” or an innovation to different potential adopters.     

Elderly activity patterns and demand for transportation in a small city setting2

Although elderly in a small city setting leave their homes for approximately the same purposes and at the same frequency as elderly in metropolitan settings, they are much more dependent on the automobile. A higher proportion of the elderly in a small city drive, but driving status did not have a significant impact on frequency of travel or the spatial extent of travel. Health status was not an important factor when other variables were taken into account, but the older elderly did take fewer trips than the younger elderly. Income, sex and residential location had modest impacts on activity patterns, but the use of a well-established Dial-a-Ride system was minimal. Variation in activity patterns among the elderly in a small city suggested continuity of behavior, a modest decline with age and a strong preference for automobile travel or walking from conveniently located housing complexes.     

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