CHIDIST compares the chi-square value to be given for a random sample that is calculated from the sum of (observed value-expected value)^2/expected value for all values with the theoretical chi-square distribution and determines from this the probability of error for the hypothesis to be tested.
CHIDIST 将某一随机样本得出的 X2 值（该值通过利用公式求得的用于所有值的数值得出）与理论上的 X2 分布进行比较，并由此计算出待检验假设的错误概率。用公式（观察值 - 期望值）^2/期望值计算所有值后再求和即可得出样本的 X2 值。