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Clustering of rare events


, : Clustering of rare events. Biometrics 39(1): 193-205

The clustering of cases of a rare disease is considered. The number of events observed for each unit is assumed to have a Poisson distribution, the mean of which depends upon the population size and the cluster membership of that unit. Here a cluster consists of those units that are homogeneous in their rate of occurrence of the rare events under study. A sample of units is modeled by a mixture of Poisson distributions, one for each cluster, the mixing parameters being the proportions of all units represented by the components of the mixture. Maximum likelihood and Bayes approaches are employed to determine criteria for separating a sample into groups of units with homogeneous rates. A likelihood ratio test for the significance of a two-component mixture is presented as an example. The performance of the criteria is illustrated with data on the spatial occurrence of sudden infant deaths (SIDs) in North Carolina counties over a four-year period. The results suggest that the practice of dividing the counties into high- and low-risk categories on the basis of the ordered rates alone should be questioned. Tests based upon combinatorial methods are also presented to examine the significance of the number of contiguous counties among those with high rates.

US$19.90

PMID: 6871348

DOI: 10.2307/2530819


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van der Kemp, W.J.M.; Wijnen, J.P.; Luijten, P.R.; Klomp, D.W.J., 2015: Saturation-transfer effects and longitudinal relaxation times of (31) P metabolites in fibroglandular breast tissue at 7T. To investigate longitudinal relaxation times and saturation-transfer effects of phosphorous metabolites in breast fibroglandular tissue in vivo with (31) P MR spectroscopy at 7T. Progressive saturation with adiabatic half passage excitation was us...

Thiers, H.; Normand, C., 1970: Trial of whiting of infantile psoriasis with the association to local treatment of a diet without lipids and of hepatocatalasis. La Revue Lyonnaise de Medecine 19(14): 559-561

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Peng, S.X.; Borah, B.; Dobson, R.L.; Liu, Y.D.; Pikul, S., 2000: Application of LC-NMR and LC-MS to the identification of degradation products of a protease inhibitor in dosage formulations. LC-NMR and LC-MS were applied to the characterization of six degradation products of a protease inhibitor, N-hydroxy-1,3-di-[4-ethoxybenzenesulphonyl]-5,5-dimethyl-[1,3]c yclohexyldiazine-2-carboxamide, in a dosage formulation. A reversed-phase HP...

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Cooter, J., 1996: A not on the late D K Kevans 1947 revision of the British species of Colon herbst. Entomologist's Monthly Magazine 132(1580-1583): 91-92

Ueda, M.; Masu, Y.; Ando, A.; Maeda, H.; Del Monte, M.A.; Uyama, M.; Ito, S., 1998: Prevention of ornithine cytotoxicity by proline in human retinal pigment epithelial cells. PURPOSE. To investigate the relationship between ornithine-delta-aminotransferase (OAT) deficiency and ornithine accumulation and the specific degeneration of retinal pigment epithelial (RPE) cells in gyrate atrophy. METHODS. Human RPE cells, huma...

Tuckett S., 1972: Study of envelope proteins in escherichia coli cet and reca mutants by sodium dodecyl sulfate acrylamide gel electrophoresis. Journal Of Supramolecular Structure: 77-97

Curran S.; Wattis J.P.; Hindmarch I., 1989: Psychometric assessment of patients with primary degenerative dementia results using choice reaction time a preliminary report. Medical Science Research 17(21): 893-894