Linear Regression DATA-SCIENCE-FOUNDATIONS Practice Questions (Page 7)

Questions 31–32

1. 31foundation · easy

   What hypothesis does the t-test for an individual regression coefficient test?

   • AH0: βi = 1 versus Ha: βi ≠ 1
   • BH0: The model has no predictive power versus Ha: The model has predictive power
   • CH0: The residuals are normally distributed
   • DH0: βi = 0 versus Ha: βi ≠ 0
   Reveal Solution Discussion Select an answer first
2. 32application · medium

   A data scientist builds a linear regression model to predict employee productivity based on hours of training. She calculates a 95% confidence interval for the mean productivity of all employees who receive 10 hours of training, and a 95% prediction interval for a single new employee who receives 10 hours of training. Which statement is true?

   • AThe intervals cannot be compared because they are based on different confidence levels.
   • BThe prediction interval is wider than the confidence interval.
   • CBoth intervals have the same width.
   • DThe confidence interval is wider than the prediction interval.
   Reveal Solution Discussion Select an answer first