Identify which assumption is needed to use the linear regression model to make inferences about the relationship. Identify which assumption is the least critical.

Identify which assumption is needed to use the linear regression model to make inferences about the relationship. Identify which assumption is the least critical.

Question
Sampling distributions
asked 2020-10-21
Identify which assumption is needed to use the linear regression model to make inferences about the relationship.
Identify which assumption is the least critical.

Answers (1)

2020-10-22
Assumptions:
- Data are collected randomly.
- A linear relationship between dependent variable y and explanatory variable x in the population.
- The population values of y at each value of x follow a normal distribution with the same standard deviation at each x value.
In this case, the third assumption is the least critical because the estimates from the regression models have bell-shaped sampling distributions when the sample size is large according to the central limit theorem.
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