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Biomedical subjects

N Wermuth

Publications and source records attributed to N Wermuth.

6 recordsLinked to original sources
PubMed1979

Detecting systematic errors in multi-clinic observational data.

In multi-clinic studies it is hard to maintain a uniformly high quality of measurement and coding. Systematic errors almost always occur, in spite of the best of intentions and the most rigid protocols. It is the statistician's responsibility to plan for the detection of these errors, as well as to try to avoid them and not be misled by them. The practice of examining the univariate and multivariate sample frequency distributions of the variables under study, with an eye open for anything that looks puzzling, can be very helpful in detecting and trying to correct systematic errors that would bias the analysis. Examples are given from a 21-clinic study on pregnancy and child development.

Humans↗
PubMed1976

Finding condensed descriptions for multi-dimensional data.

We describe two programs that may be used to find condensed descriptions for data available in a contingency table or in a covariance matrix in the case that these data follow a multinomial or a multivariate normal distribution, respectively. The programs perform a stepwise model search among multiplicative models by computing appropirate likelihood-ratio test statistics.

Computers↗
PubMed1976

[Remarks on configuration frequency analysis].

The "Konfigurationsfrequenzanalyse" (KFA) is a method proposed by Lienert to detect syndromes. Using examples we criticize the definition of a syndrome used for a KFA, and we thus criticize the interpretation of the results of a KFA. Furthermore, we describe briefly a backward selection procedure of multiplicative models for contingency tables. This procedure may be used to find simple patterns of association for several symptoms.

Diagnosis, Differential↗
PubMed1975

Some determinants of the migration of professional manpower.

Determinants of migration of professional manpower are investigated using data from a 1970 survey of immigrants to the United States. From a respondent's stated "intent to stay" in the United States and five other characteristics a six-dimensional contingency table is formed. We find a well-fitting log-linear model for this table. Thus, we establish the importance of selected determinants of migration and present a table of predicted rates of intent to stay in the United States.

Adult↗