Chi-square value can never be negative becausea. The observed frequencies cannot be negativeb. Difference between observed &amp; expected frequencies is squaredc. The sum of the difference is computedd. Observed frequency is always greater than expected frequency

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Chi-square value can never be negative becausea. The observed frequencies cannot be negativeb. Difference between observed &amp;amp; expected frequencies is squaredc. The sum of the difference is computedd. Observed frequency is always greater than expected frequency

bridged4xi · Accepted Answer

Chi-Square Test: In statistical hypothesis test, a chi-square test, or specifically Pearson&#039;s chi-square test is performed when the test statistic is distributed as chi-square under the null hypothesis. This test is used to determine whether there is a significant difference between the observed and the expected frequencies in one or more categories of a contingency table.In the standard applications of this test, the observations are classified into mutually exclusive classes. If the null hypothesis is true i.e. there are no significant differences between the classes in the population, the test statistic which is computed from the observations follows a chi-square frequency distribution. The purpose of the test is to determine how likely the observed frequencies would be assuming the null hypothesis is true.If Oi and Ei be the observed and expected frequency for the ith category, then the chi-square test statistic is given by,χc2=∑i(Oi−Ei)2EiFrom the above formula of chi-square, it is clear that being the square of the difference between observed and expected frequencies, the numerator cannot be negative. Also, the denominator is the expected frequency, so, it cannot be negative also.Therefore, the correct answer is: Option b.

skuleborn2de · Accepted Answer

Option a. is incorrect because it does not depend on the observed frequencies whether the value of chi-square will be positive or negative.Option c. is incorrect because here the sum of square of the difference is calculated, not sum of difference.Option d. is incorrect because observed frequencies cannot be always greater than the expected frequencies as the sum of both are same.

Chi-square value can never be negative because a. The

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