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Lyle W Konigsberg

Publications and source records attributed to Lyle W Konigsberg.

5 recordsLinked to original sources

Statistical basis for positive identification in forensic anthropology.

Forensic scientists are often expected to present the likelihood of DNA identifications in US courts based on comparative population data, yet forensic anthropologists tend not to quantify the strength of an osteological identification. Because forensic anthropologists are trained first and foremost as physical anthropologists, they emphasize estimation problems at the expense of evidentiary problems, but this approach must be reexamined. In this paper, the statistical bases for presenting osteological and dental evidence are outlined, using a forensic case as a motivating example. A brief overview of Bayesian statistics is provided, and methods to calculate likelihood ratios for five aspects of the biological profile are demonstrated. This paper emphasizes the definition of appropriate reference samples and of the "population at large," and points out the conceptual differences between them. Several databases are introduced for both reference information and to characterize the "population at large," and new data are compiled to calculate the frequency of specific characters, such as age or fractures, within the "population at large." Despite small individual likelihood ratios for age, sex, and stature in the case example, the power of this approach is that, assuming each likelihood ratio is independent, the product rule can be applied. In this particular example, it is over three million times more likely to obtain the observed osteological and dental data if the identification is correct than if the identification is incorrect. This likelihood ratio is a convincing statistic that can support the forensic anthropologist's opinion on personal identity in court.

Age Determination by Skeleton↗

Estimation of the most likely number of individuals from commingled human skeletal remains.

This study examines quantification techniques applicable to human skeletal remains, and in particular the Lincoln index (LI), the minimum number of individuals (MNI), and what we refer to as the most likely number of individuals (MLNI), which is a modification of the LI by Chapman ([1951] Univ. Calif. Publ. Stat. 1:131-159). As part of the study, a test of pair-matching between commingled homologous elements, e.g., right and left femora, was performed based on gross morphology. The results show that pair-matching can be accurately performed, and that the MLNI is a useful technique for dealing with well-preserved commingled remains recovered from archaeological excavations and/or forensic investigations. Our results show that it is potentially misleading to draw population conclusions based on the MNI, except in instances where recovery is near 100%. The MLNI was found to be the best method to compensate for the potential underestimates of the MNI and potential bias in the original LI estimates resulting from small sample sizes. We demonstrate the use of MLNI in estimating the number of individuals from Lodge 21 at the Larson site, a late protohistoric structure at which the inhabitants were massacred and subsequently had their skeletal elements commingled by further taphonomic processes. We also show how to calculate estimates and standard errors for the recovery probabilities of skeletal elements.

Bone and Bones↗

Deconstructing death in paleodemography.

In 1992 in this Journal (Konigsberg and Frankenberg [1992] Am. J. Phys. Anthropol. 89:235-256), we wrote about the use of maximum likelihood methods for the "estimation of age structure in anthropological demography." More specifically, we presented a particular method (the "iterated age-length key") from the fisheries literature and suggested that the method could be used in human and primate demography and paleodemography as well. In our paper (section titled "Some Future Directions"), we spelled out two broad areas that we expected to see develop over the ensuing years. First, we felt that the use of explicit likelihood methods would open up interest in basic estimation issues, such as the calculation of standard errors for demographic estimates and the formulation of tests for whether samples differed in their demographic structure. Second, we felt that the time was ripe for hazards analyses that would incorporate the uncertainty in estimation that follows from using age "indicators" rather than known ages. While some of these developments have occurred during the last decade, few have been reported in the American Journal of Physical Anthropology. In this paper we resolve some issues from our 1992 paper, and attempt to redress this deficit in the literature by reviewing some recent developments in paleodemography over the past decade.

Adult↗

New formulae for estimating stature in the Balkans.

Recent studies of secular change and allometry have observed differential limb proportions between the sexes, among and within populations. These studies suggest that stature prediction formulae developed from American Whites may be inappropriate for European populations. The purpose of this investigation is to present more appropriate stature prediction equations for use in the Balkans to aid present-day identifications of the victims of genocide. The reference sample totals 545 white males obtained from World War II data. The Eastern European sample totals 177 males and includes both Bosnian and Croatian victims of the recent war. Mean stature for Eastern Europeans was obtained from the literature. Results show that formulae based on Trotter and Gleser systematically underestimate stature in the Balkans. Because Eastern Europeans are taller than American Whites it is appropriate to use this as an "informative prior" that can be applied to future cases. This informative prior can be used in predictive formulae, since it is probably similar to the sample from which the Balkan forensic cases were drawn. Based on Bayes' Theorem new predictive stature formulae are presented for Eastern Europeans.

Adult↗