Bioassay of kinship in northwestern Europe.

Kinship of Barra (Outer Hebrides) is bioassayed as 0.0096 relative to northwestern Europe, in reasonable agreement with prediction of 0.008 relative to Britain.

Causal analysis of academic performance.

Maximum likelihood methods are presented to test for the relations between causes and effects in linear path diagrams, without assuming that estimates of causes are free of error. Causal analysis is illustrated by published data of the Equal Educational Opportunity Survey, which show that American schools do not significantly modify socioeconomic differences in academic performance and that little of the observed racial difference in academic performance is causal. For two races differing by 15 IQ points, the differential if social class were randomized would be only about 3 points.

A mapping function for man.

Assuming a perfect correspondence between the site of crossing-over and an observed chiasma, data on meiosis in the human male are used to estimate a mapping parameter which on average turns out to be intermediate between the Kosambi and Carter-Falconer values, but smaller for acrocentrics. A table is given for converting recombination frequencies to map distances.

A chiasma map of man.

By fitting compounds beta distributions to chiasma frequencies the physical map obtained from banded chromosomes has been converted into a chiasma map giving the distribution of observed chiasmata in relation to several hundred cytological bands, assuming proportionality of mitotic and meiotic chromosomes. This is a genetic map if there is a precise correspondence between sites of chiasmata and crossing-over. However, if there is appreciable preanaphase movement of chasmata, then the chiasma map is a serious distortion of the genetic map.

Commingling in distributions of lipids and related variables.

In a sample of nearly 8,000 Japanese males, the distributions of casual cholesterol and triglyceride, hematocrit, glucose, uric acid, diastolic blood pressure, and weight (covariance adjusted) could not be normalized by a power transform and were significantly better fitted by a mixture of distributions. The evidence for admixture was nonsignificant for systolic blood pressure, significant but unimpressive for height and weight, and strong for the remaining variables. The minor component corresponded to high values, in low frequency except for triglyceride and glucose.

Fabrication of pH-sensitive implantable electrode by thick film hybrid technology.

We report preliminary results of our experiments directed at fabricating pH-sensitive electrodes suitable for in vivo use by means of thick film screening techniques. Our results show that glass membranes of suitable thickness and possessing nearly theoretical sensitivity to pH can be fabricated by this process. A hybrid electrode structure permits the incorporation of a source follower FET amplifier directly adjacent to the pH membrane, significantly reducing response time and noise pick-up.

An inferred chiasma map of Drosophila melanogaster.

The chiasma map of D. melanogaster is inferred from the genetic map, giving correspondences between physical and genetic locations. Crossing-over is reduced near the centromere and telomeres.

Skewness in commingled distributions.

A likelihood ratio test is given for distinguishing skewness from commingled distributions, using a power transform to remove skewness appropriately for each of the alternatives tested. The alternative hypotheses postulate that the transformed data are from one normal or a mixture of two or three normal homoscedastic distributions. Since each mixture has unique asymmetry, skewness is estimated simultaneously with the means, proportions and variance of components.

Resolution of cultural and biological inheritance by path analysis.

Analysis of family resemblance is developed in terms of three genetic parameters, six parameters for cultural inheritance, and one parameter for an index estimating family environment. With efficient use of nuclear families the model is fully determinate. Other biological and social relationship provide additional degrees of freedom for testing goodness of fit.

Population structure of Barra (Outer Hebrides).

Historical demography, surname concordance (isonymy), migration, and genealogy give a consistent description of population structure. The census size has averaged about 1400 over the last five centuries. Conjoined with an effective migration rate of 3-05 per generation as estimated by three different methods, this gives an evolutionary size of 638, random kinship of 0-008 and inbreeding of 0-007 relative to the rest of Britain.

Analysis of family resemblance. V. Height and weight in northeastern Brazil.

Sib correlations for height and weight decrease with absolute age difference. Parent-child correlations increase with age of child, with greater resemblance to the mother than the father. Estimates of the relative variance due to common environment are greater, and heritability estimates less, than for earlier studies.