Learning from Jelly - Chi Square

Q: Why and when should we use Chi Square in analysis?

A: We use Chi Square if no known distribution in the data. Generally, in the nature arena, such as height and weight of people, length of rabbit ear can form a perfect bell-shape graph. However, data we get from research will hardly fall into any normal distribution. For example, distribution of income level in the population usually skews towards lower the tier. Since we cannot expect a normal distribution, we can use Chi-Square to check the pattern.

Exception Analysis (Tukey) is calculated by Chi Square.

??? Correct me if I am wrong.