Student-t deviate corresponding to a given normal deviate

Abstract We consider statistical criteria for partitioning a reference database to obtain separate reference ranges for different subpopulations. Using general formulas relating population variances, sample sizes, and the normal deviate test for the significance of the difference between two subgroup means, we show that partitioning into separate ranges produces little reduction in between-person variability, even when the differences between means are highly significant statistically. However, when there is a clear physiological basis for distinguishing between certain subgroups, simulation studies show that partitioning may be necessary to obtain reference limits that cut off the desired proportions of low and high values in each subgroup. Guidelines based on these results are provided to help decide whether separate ranges should be obtained for a given analyte.

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Pre-Therapy Adaptation of Stuttering and Its Relation to Speech Measures of Therapy Progress

Journal of Speech and Hearing Research ◽

10.1044/jshr.1104.740 ◽

1968 ◽

Vol 11 (4) ◽

pp. 740-746 ◽

Cited By ~ 6

Author(s):

David Prins

Keyword(s):

Negative Correlation ◽

Oral Reading ◽

Partial Correlation ◽

Correlation Coefficients ◽

Speaking Rate ◽

Normal Deviate ◽

Adaptation Measures ◽

Negative Direction ◽

Therapy Program ◽

Post Therapy

Three measures of stuttering adaptation were obtained on 20 stutterers prior to the beginning of an eight-week residential therapy program. Following therapy each subject was evaluated using six scores which represented changes in speaking rate and frequency of stuttering during oral reading and in self-formulated speech. The results showed that less than half of the stutterers demonstrated a significant adaptation trend (A t ), and only 12 of 20 showed significant normal deviate scores (A s ) of adaptation. Partial correlation coefficients were significant in a negative direction between pretherapy percentage (A p ) and trend (A t ) adaptation measures and post-therapy scores showing increment in reading and speaking rate. It appears that adaptation is neither consistendy nor highly related to speech measures of therapy progress. A rationale is suggested for the negative correlation of adaptation and therapy change scores.

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The Normal Deviate Test of Phylogenetic Value of a Data Matrix

Systematic Biology ◽

10.1093/sysbio/38.1.51 ◽

1989 ◽

Vol 38 (1) ◽

pp. 51-54

Author(s):

W. J. Le Quesne

Keyword(s):

Data Matrix ◽

Normal Deviate

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Algorithm 267: random normal deviate [G5]

Communications of the ACM ◽

10.1145/365628.365649 ◽

1965 ◽

Vol 8 (10) ◽

pp. 606 ◽

Cited By ~ 10

Author(s):

M. C. Pike

Keyword(s):

Normal Deviate

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Normal Deviate Analysis of Mortality Statistics

Japanese Journal of Health and Human Ecology ◽

10.3861/jshhe.30.74 ◽

1964 ◽

Vol 30 (4) ◽

pp. 74-79

Author(s):

Minoru UEMATSU

Keyword(s):

Normal Deviate ◽

Mortality Statistics

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Wais—r Scatter with Psychiatric Inpatients: II. Intersubtest Scatter,

Psychological Reports ◽

10.1177/00332941930733pt121 ◽

1993 ◽

Vol 73 (3_part_1) ◽

pp. 851-860 ◽

Cited By ~ 4

Author(s):

Daniel E. Boone

Keyword(s):

Psychiatric Inpatient ◽

Psychiatric Inpatients ◽

Normal Deviate ◽

Verbal Scale ◽

Clinical Literature ◽

Variability Index ◽

And Performance ◽

Performance Scale

Intersubtest scatter values for the Full, Verbal, and Performance Scales of the WAIS—R were estimated for a sample of 163 psychiatric inpatients and compared with those reported for the WAIS—R standardization group using the normal deviate (z) test. Intersubtest scatter was assessed using the range and the Profile Variability Index. Results were surprising and conflicted with what was expected based on the clinical literature. First, in comparison to the standardization group, the psychiatric inpatients showed significantly more intersubtest scatter on the Verbal Scale only, while Performance Scale values were comparable. Second, the psychiatric inpatient sample, as a group, showed identical amounts of scatter on the Verbal and Performance Scales. Results suggest that the interpretation of intersubtest scatter as a sign of psychopathology should be avoided.

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