Gw mau tau Example dari Uji kuadrat-chi Pearson. Jelasin dalam bahasa sunda

For example, to test the hypothesis that a random sample of 100 péople has been drawn from a population in which men and women are equal in frequency, the observed number of men and women would be compared to the théoretical frequencies of 50 men and 50 women. If there were 45 men in the sample and 55 women, then

If the null hypothesis is true (i.e., men and women are chosen with equal probability in the sample), the test statistic will be drawn from a chi-square distribution with one degree of freedom.  Though one might expect two degrees of freedom (one éach for the men and women), we must take into account that the total number of men and women is constrained (100), and thus there is only one degree of freedom (2 − 1).  Alternatively, if the male count is known the female count is determined, and vice-versa.

Consultation of the chi-square distribution for 1 degree of freedom shows that the probability of observing this difference (or a more extreme difference than this) if men and women are equally numerous in the population is approximately 0.3. This probability is higher than conventional criteria for statistical significance, so normally we would not reject the null hypothesis that the number of men in the population is the same as the number of women.