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K D Wernecke

Publications and source records attributed to K D Wernecke.

8 recordsLinked to original sources
PubMed1992

A coupling procedure for the discrimination of mixed data.

A procedure is described for coupling different discriminators to a new (common) decision rule using the corresponding allocation vectors only. This enables one to cope jointly with data of different structure and/or scales of measurement but without strong restrictions on the number of (especially categorical) features. The method is combined with a consequent cross-validation process securing the results reached. Examples from medical diagnostics demonstrate the usefulness of the proposed procedure, especially in comparison with the known linear discriminant analysis as judged from the error rates obtained.

Diagnosis↗
PubMed1990

[A computer-assisted system for diagnosing rhinologic function].

We describe the new computerized rhinologic diagnostic system "CARIMA", a software-controlled system based on a measuring head and a PC. The currently available software allows active anterior rhinomanometry to be carried out with a special program for the nasal allergen test, as well as active posterior rhinomanometry and the determination of the laryngotracheal resistance in patients with an open tracheostoma. The measurement procedure is controlled by the patient by watching the screen during data collecting. The breaths are averaged after curve correction by splining, introducing a time-referred system into the computerized rhinomanometry. The advantage of the method is a detailed analysis of the increasing and decreasing part of the inspiratory and exspiratory half-wave, allowing clinical conclusions to be made about the nasal valve.

Airway Resistance↗
PubMed1978

[Multivariate variability investigations of acoustically evoked slow potentials (AEP) (author's transl)].

By means of the multivariate variance analysis the ratio of intra- and interindividual variability of the AEP--time function was investigated. 90 AEP from 9 normal hearing persons (10 AEP from every person, averaging sessions spread over 10 weeks) were analyzed. The 10 AEP of every person were treated as a random sample. A multivariate pair comparison (single comparison between samples) on the basis of 12 variables (time points) showed only for 1 out of 36 sample pairs no significant differences between the sample averages. By applying the discriminant analysis false classifications resulted only for 7 out of the 90 AEP (approximately 8%). These facts mean, that even throughout the time of 10 weeks the intraindividual differences of the AEP--time behavior are significantly smaller than the interindividual ones.

Acoustic Stimulation↗
PubMed1977

[The proof of age differences of slow acoustically evoked potentials of adults by a multivariate statistical analysis (author's transl)].

Many authors consider the nature of the slow acoustically evoked potentials to be partly a specific one. Therefore the AEP-time behavior probably contains more information about the functional state of the acoustical channel than it is got by the usual measurement of only 3 values (N1P2-amplitude, 2 latencies). A test of this hypothesis is possible with a multivariate mathematical procedure, which involves the whole AEP-time behavior. We are using the multivariate variance- and discriminant analysis. For the application of this statistical method random samples of patients with certain otologic diseases are needed. To avoid mistakes in grouping these samples some preliminary investigations had been necessary: This paper reports the results of multivariate investigations concerning age differences of the AEP in normal hearing adults. By means of the multivariate variance analysis the AEP of 3 age groups were examined (group 1: 15--34 years, group 2: 35--44 years, group 3: 45--60 years). At 1000 Hz as well as at 400 Hz significant differences between the group averages were found, which were not detectable by the usual N1P2-amplitude measurement. Furthermore with the discriminant analysis it is possible to perform a relatively reliable differentiation between the individual AEP of the age groups 1 and 3.

Acoustic Stimulation↗
PubMedDate not supplied

[The ERA characteristics in normal-hearing persons].

The ERA characteristics (amplitudes and latencies) were measured in normal-hearing adults (20 to 25 years of age) at frequencies of 500 Hz, 1000 Hz and 4 000 Hz. Two other age groups (30 to 50 and 55 to 70 years of age) were measured only at 1 000 Hz. Contrary to other authors, the linear scale was chosen to represent the amplitudes. In calculating the variances of the amplitudes it turned out that the intra-individual variance is significantly below the inter-individual variance. Expressed in per cent as a variational coefficient, both decrease with increasing stimulus intensity. Contrary to the behaviour of the amplitudes, no significant difference between the intra- and inter-individual variational coefficient of the latencies could be found. The same is valid for the variational coefficients of the N1 and P2 latencies. As a function of the stimulus strength, the variational coefficient passes through a minimum at medium stimulus intensity. Within the investigated range of 20 to 70 years of age, no significant differences of amplitudes and latencies between the age groups could be found.

Acoustic Stimulation↗