chi-square distribution

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chi-square dis·tri·bu·tion

a variable is said to have a chi-square distribution with K degrees of freedom if it is distributed like the sum of the squares of K independent random variables, each of which has a normal (gaussian) distribution with mean zero and variance one. The chi-square distribution is the basis for many variations of the chi-square(d) test, perhaps the most widely used test for statistical significance in biology and medicine.
References in periodicals archive ?
Table-II: Significant effects of confounding variable of Maternal Age on outcomes of (A) Blood loss (B) Pain, and (C) Need for surgical intervention as depicted by p-values of chi square and exact tests.
As the Chi Square value was found greater than the table value at 0.05, hence the statement was found significant and was accepted.
Table 3 presents a summary of the forms included in these two classes, that is, their 35 most representative forms, showing the frequency of each form in the class, its total frequency in the analyzed segments, the percentage of the form in the class, and the value of its chi square of association, calculated from a table such as Table 1 (for each value, df= 1;N= 622, p < .001).
The table also shows that the chi square value X2 pless than 0.05, df (1) = 0.29 is less than the corresponding critical value (3.84).
Table 3, shows the Pearson Chi square data of the association between age, gender, educational qualification and religion on the attitudes of the respondents towards SCD and SCD premarital counseling.
Sample size: 284 Degrees of Freedom: 5 Significance Level ([alpha]): 0.05 Critical [[chi square].sub.0.05,5] 11.07 (from tables) Table 8: Summary of Chi Square Analysis.
Over one third of Haitian clients (37 percent) waited more than 2 months or longer before beginning to receive services as opposed to 8 percent of Hispanic clients (Chi Square 10.346, p < .01).
This difference was statistically significant, Chi square (1, N = 35) = 24.08, p = .02.
A Chi Square analysis was not possible due to cell size restrictions.
Statistically significant chi square (or difference of chi square) statistics occur because of the large sample sizes.