9/28/2016

Questions on the sampling distribution of the sample mean

Statistical Inference 

• Point Estimation
• Confidence Intervals: point estimator ± margin of error

Definition: A 100*C% confidence interval (C.I.) for a parameter (say theta) is given by two statistics  L and U such that P(L<= theta <= U) = C.

• Derivation of a CI for mu
• Computing CIs with R - see zCI.R

Class Activity to understand computation and behavior of CIs

• The behavior of C.I.'s
  • Use zCI.R to compute a CI for mu.
  • Does the CI from your simulated data contain mu?
  • Verify the caclulations by checking the interval given for the first sample.
  • How many of the C.I.'s for the class contain the true mean?
• How does this simulation exercise help you interpret confidence intervals?

Complete the Confidence Intervals Lab on openintro.org

Please read Sections 4.3 - 4.5 for class on Friday.