Lec28 Sampling Distributions and Standard Errors
Understanding how sampling variability affects estimates.
Announcements
- Problem Set 10 due at 5pm
todayTuesday 11/29 - Office hours
- Today 1pm-4pm
- Tuesday 9am-12pm
Thought Experiment
Sample 3 students at random and get their (sample) mean age.
Results: Based on set.seed(41)
, Luisangel’s favorite number.
- Question: Why do the sample means below vary?
- Answer: Because of the sampling variability induced by the random sampling!
Random Sample | (Sample) Mean Age |
---|---|
Jack, Jared, Sam | 21.7 |
Wengel, Rebecca, Steven | 19.4 |
Stefan, Joccelyn, Sierra | 20.0 |
In-Class
- Lec27-B learning check discussion
- Handout based on second figure of LC above
- Chalk talk on
- Sampling distributions
- Standard errors