New Estimates of Undocumented Mexican Migration and the Probability of Apprehension*

Using a new source of data, we estimate the probability of apprehension among Mexican migrants attempting to cross into the United States without documents. Over the period 1965-1989 we found an average apprehension probability of .35, confirming earlier estimates. We then applied annual probabilities to estimate the gross volume of undocumented Mexican migration and adjusted these figures to derive estimates of the net undocumented inflow.     

The protection of children exposed to marital violence

A review of the available research shows that children who witness violence between their parents have emotional and behavioural difficulties that mirror those of children currently identified as being abused. It is not clear whether these difficulties stem from the violence itself or the insecurity common in such families. However, current understanding of the experience of trauma suggests that some of these children are traumatized by the scenes they witness. Thus they fulfil the criteria for suffering from ‘significant harm’, within the guidelines of the Children Act. Current models of intervention in other areas of identified abuse could be applied to these children, offering adequate protection from further harm.     

A demonstration of the effect of seasonal migration on fertility

Fertility estimates were calculated using own children data from the Mexican migrant town of Guadalupe, Michoacan. In this town, 75 percent of families have a member working in the United States, and wives are often regularly separated from their migrant husbands. Simulations by Menken (1979) and Bongaarts and Potter (1979) suggest that fertility among these women should be depressed. Our results confirmed this hypothesis, showing that the seasonal absence of migrant husbands disrupted both the level and timing of fertility. However, the effect was greater for legal than for illegal migrants, a pattern that stemmed from social factors as well as physical separation. A logistic regression analysis showed that reductions in birth probabilities are greater the longer a couple is separated, and that these reductions are in the range expected from prior simulations.     

The effects of alternating mand and tact training on the acquisition of tacts

Two training procedures were compared with respect to the average number of training trials it took to teach new verbal responses to normal children. Mand contingencies were alternated with tact contingencies in one condition while only tact contingencies were in effect in the other condition. Normal, preschool children served as subjects and toy parts were the objects that were to be named. The results indicated that it took, on the average, fewer trials to teach part names (tacts) in the mand-tact condition than in the tact only condition. Although more research is needed to confirm this, it appears that mand contingencies involve stronger controlling variables and can facilitate the acquisition of a tact repertoire.

     

EXACT TWO-SAMPLE MEDIAN TESTS WHEN ONE "SAMPLE" VALUE POSSIBLY FROM A DIFFERENT POPULATION

Random samples are assumed for the univariate two-sample problem. Sometimes this assumption may be violated in that an observation in one “sample”, of size m, is from a population different from that yielding the remaining m—1 observations (which are a random sample). Then, the interest is in whether this random sample of size m—1 is from the same population as the other random sample. If such a violation occurs and can be recognized, and also the non-conforming observation can be identified (without imposing conditional effects), then that observation could be removed and a two-sample test applied to the remaining samples. Unfortunately, satisfactory procedures for such a removal do not seem to exist. An alternative approach is to use two-sample tests whose significance levels remain the same when a non-conforming observation occurs, and is removed, as for the case where the samples were both truly random. The equal-tail median test is shown to have this property when the two “samples” are of the same size (and ties do not occur).     

Tailored program evaluation: Past, present, future

This paper discusses measurement issues related to the evaluation of computer-tailored health behavior change programs. As the first generation of commercially available tailored products is utilized in health promotion programming, programmers and researchers are becoming aware of the unique challenges that the evaluation of these programs presents. A project is presented that used an online tailored health behavior assessment (HBA) in a worksite setting. Process and outcome evaluation methods are described and include the challenges faced, and strategies proposed and implemented, for meeting them. Implications for future research in tailored program development, implementation, and evaluation are also discussed.     

Shaping the future of social work in end-of-life and palliative care

The second Social Work Summit on End-of-Life and Palliative Care was held from June 1 to June 3, 2005. Sixty representatives of more than 35 social work and other professional organizations with a commitment to improve care for the terminally ill, dying, and bereaved, attended and formulated key priority directions and initiatives that will further the field.