Dean Harper

Local Dependence Latent Structure Models.

AbstractA local independence latent structure model, which assumesm latent classes, requires a minimum of 2m-1 items for the solution of the 2m2 latent parameters. If one adds 3 items to the test and if one assumes local “dependence” between pairs of items, thereby adding

Migrant farm workers: social conditions, adaptive belief systems, and psychiatric care.

\left( {\begin{array}{*{20}c} {2m + 2} \\ 2 \\ \end{array} } \right)

Exploitation in Migrant Labour Camps

additional latent parameters, ξij, representing the association between itemsi andj, then it is possible to obtain estimates for all of the latent parameters: latent class frequencies latent probabilities, and measures of association between pairs of items. The solution consists of (1) forming (m + 1) × (m + 1) matrices of manifest data, which are singular, (2) solving for the ξij in equations that result from the singularity of the data matrices, (3) “correcting” the manifest data by removing the “contamination” due to local dependence, and (4) estimating the remaining latent parameters from the corrected data, using methods outlined in earlier literature.

The computer simulation of sociological surveys

Social life is filled with problems — situations that are perceived and defined as problems by individuals as they interact with each other. As such, these problems are often of more concern to those individuals than are other matters. The sociologist can gain insight into the structure of social relations by focusing the investigation on those problems rather than directly on the underlying structure. That is, the discussion of the problems that those being studied see in their situation or setting is revealing of the structured relations in those settings. This approach to doing social research is illustrated by two of the authors studies — one a study of an emergency department, and the second a study of how commercial art galleries affect the production and consumption of art.

The Growth of Bureaucracy in School Systems

Two migrant farm labor camps were observed during two summer harvesting seasons. A part of the observations consisted of interviews with 104 farm laborers, with 16 of them being interviewed intensively. Migrant farm workers were exploited by the crew boss and the farm owner, and they in turn exploited each other. Consequently, many workers left farm work. Those who remained in the camps adapted their attitudes and their views to the conditions. Though they had a begrudging respect for the crew boss, they showed an overriding concern with exploitation. They conveyed a numbness about life, themselves, and their place in society; this numbness was combined with self-criticism and an attempt to maintain some self-respect. They expressed distrust for and suspicion of others, and though they could not articulate it very well, they felt great fear and anxiety. In order to diagnose and treat disorder in migrant farm workers, psychiatrists must understand the exploitive social setting of migrant farm work and the adaptations of workers to that setting.

Work Behavior in a Service Industry

In sociological surveys, respondents occasionally give false answers to factual questions which inquire if the respondent has some attribute. The social scientist may wish to correct estimates of the proportion of respondents having the attribute or he may wish to know the amount of error which is occurring in his survey. These two objectives can be achieved by a probabilistic model which assumes (1) that respondents have some probability of giving false information, and (2) that if respondents are queried about the attribute on two or more occasions, among those with the attribute, there is statistical independence in their responses, as is also the case for those without the attribute. With further simplifying assumptions, the social scientist can estimate the probability ofgiving false information and the true proportion of respondents with the attribute.