Z-value


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Z-value

(in statistics) indicates how many STANDARD DEVIATIONS away from the MEAN a value resides. For a given set of data the mean (x) is subtracted from each member (x) of the set; then each member is divided by the standard deviation (s) of the set: z = (x - x)/s. A positive score indicates the value is above the mean, a negative score indicates below. Z-values are useful in comparing sets of data with different means and standard deviations.

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All the patients were having ALT value more than 150 IU/L with mean SGPT was 1202.2 [+ or -] 867.587 U/L (z-value: 6.64 and p-value <0.0001; statistically significant).
TABLE 1 Effect of the number of larvae and nymphs included in the pools on the probability of detecting Ricketssia spp Range of pool size for larvae: 3-55 Factor Coefficient SE Z-value P Intercept -0.14 0.85 -0.17 0.865 Pool size 0.00 0.02 0.09 0.926 Range of pool size for larvae: 3-1427 Factor Coefficient SE Z-value P Intercept 0.23 0.36 0.65 0.517 Pool size -0.00 0.00 -0.73 0.462 Range of pool size for nymphs: 3-51 Factor Coefficient SE Z-value P Intercept -1.23 0.58 -2.14 0.0325 Pool size 0.20 0.08 2.35 0.0190 The analyses were conducted for two groups of larvae that differed in the range of larvae included in the pools.
The second model was calculated with data from motor performance tests (motor performance model, two variables) and used the mean z-value of general motor performance items (YY, CMJ, 40 m, AG) and the mean z-value of technical skill items (DR, PA, JU).
In any [P.sub.R]-mode run, although the z-value has been ignored by the computer, subsequent comparison will reveal that it matches the generated post-halt value.
Table 6 Regression Coefficients of the Multiple Linear Regression Model Predicting Attitude Toward Local Food and Total Variance Associated with Attitude Toward Local Food within Each Treatment Group Group Variables [beta] t p Local Economy (Constant) 107.06 .00 ** Treatment Z-value of ECO .43 5.84 .00 ** Z-value of SOC .24 3.25 .00 ** Social Connection (Constant) 111.58 .00 ** Treatment Z-value of ECO .65 10.29 .00 ** Z-value of SOC .09 1.46 .15 Group [R.sup.2] Adjusted F Model p [R.sup.2] Local Economy .380 .374 64.89 .00 ** Treatment Social Connection .513 .509 113.14 .00 ** Treatment
Once the Z-value and P value have been calculated, we can say that there is enough evidence for all values below the critical value Z or -1.645; we can reject the null hypothesis and we can state that the mean of the proposed method with perturbation is lower than the mean of the other method without perturbation with a 95% of confidence and this Z-value is shown in Table 8.
Attributes Coefficients(SE) Z-Value Moderate Premium 0.40504 (0.04139) 9.787 Maximum Premium 0.16194 (0.04264) 3.798 Prompt Claims 0.52872 (0.03424) 15.442 Satisfactory Customer Service -0.05928 (0.03432) -1.727 Proximity Near 0.23173 (0.03435) 6.747 Constant -0.48887 (0.03775) -12.950 Number of observations 5600 AIC 7380.1 Likelihood ratio [chi square] 395.14 Prob> [chi square] 0.0000 Attributes P-Value [95% Conf.
Mean balanced accuracies and mean specificities of Z-value aggregations were always higher than those of the respective Westgard-like algorithms.
of elderly receiving Care provider financial support (%) practical care (%) At least one 211 (57.7) 254 (69.4) relative Daughter-in-law 9 (2.46) 240 (65.57) Son-in-law 86 (23.49) 20 (5.46) Grandchild 24 (6.56) 54 (14.75) Sibling(s) 151 (41.25) 17 (4.64) Others 27 (7.38) 17 (4.64) Table 6 Estimation result for the elderly receiving financial support and personal and practical care from spouse and children Financial support Dependent variable Marginal effect Explanatory variable Estimate z-value Age -0.005 (**) -1.92 Gender 0.009 0.19 Marital status 0.089 (*) 1.64 Education -0.096 (**) -2.46 Previous job -0.018 -0.38 Source of income 0.354 (***) 6.22 Living arrangement 0.066 1.18 Sociability 0.004 0.13 No.
These studies generally consider the regional and temporal variations of seismotectonic b-value, seismic quiescence Z-value, and some other statistical parameters for the analysis of earthquake behaviors, and their possible usage as precursors.
We performed a post hoc analysis when the Chi Square test turned out to be significant; this was done in a similar way as proposed by Beasley & Schumacher [12] using the corrected residuals (z-value).