What is the chi-square test? When do we use this?

1.	What is the chi-square test? When do we use this?
Answer» When we want to find out the statistical significance between two variables, then the chi-SQUARE test is used to UNDERSTAND the deviation between observed and expected frequency and divided by the expected frequency. Probability of 0: It indicates that both categorical variables are dependent Probability of 1: It shows that both variables are independent. Probability LESS than 0.05: It indicates that the RELATIONSHIP between the variables is significant at 95% confidence. The chi-square test statistic for a test of independence of two categorical variables is found by: Square of X = Sum[Square of (O - E) / E] Where O – Observed frequency E – Expected frequency under the null hypothesis We use this between two Categorical variables.

Answer»

When we want to find out the statistical significance between two variables, then the chi-SQUARE test is used to UNDERSTAND the deviation between observed and expected frequency and divided by the expected frequency.

Probability of 0: It indicates that both categorical variables are dependent
Probability of 1: It shows that both variables are independent.
Probability LESS than 0.05: It indicates that the RELATIONSHIP between the variables is significant at 95% confidence. The chi-square test statistic for a test of independence of two categorical variables is found by:
- Square of X = Sum[Square of (O - E) / E]
- Where O – Observed frequency
- E – Expected frequency under the null hypothesis

We use this between two Categorical variables.

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What is the chi-square test? When do we use this?

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