Easy stats questions

1.What is VIF test used for?

2.When should we use a Poisson regression?

3.When should we use mixed-effects model?

4.What estimator and statistical test should you use to test if survival curves of two groups are significantly different from each other?

5.Explain what an interaction is.

6.Explain why a test with 100% specificity might not be a perfect test (or might not even be a good test).

7.Give an example of interval-censored observation in survival analysis.

8.How many dummy variables you would need to include in the regression analysis to represent a variable with k categories?

2-3 sentences for each. do NOT use outside sources