z-test


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z-test

a statistical test using normalized data (z-values) to determine if differences in proportions between sets of data or between individual members of different sets of data are large enough to be statistically significant.
References in periodicals archive ?
The data were recorded and analyzed by SPSS software 17 version using Z-test and chi square test and a value of p<0.
Z-test was used for significance and Spearman test was used to see the association between patients' satisfaction and age, level of education, number of admissions, waiting time for doctor after admission and number of days at hospital while chi-square test was used to see the significant association between patients' satisfaction and type of admission, marital status and gender.
denotes significant change in percentage according to Z-test for proportions at p=0.
However, some authors claim that the Z-test and the [chi square]-test present a problem when significantly large samples are used, defined as the "excess power" problem (Nigrini & Mittermaier, 1997; Nigrini, 2000; Krakar & Zgela, 2009).
if abundance indices and mark--resight estimates change at the same rate over time (slopes < 1, for example, suggest a saturation effect: Caughley 1977), we used the Z-test to check if beta values of the linear models were significantly different from 1.
The z-test for proportions was used to determine the significance of the difference in mortality between male and female patients admitted to the unit.
Reliability of calculated preferences were verified by Bonferroni Z-test (Z(2) = 2.
Z-test for difference between two proportions was applied for statistical significance.