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Project

Introduce project

Tea with a TA

Hang out with the TAs from STA 199! This is a casual conversation and a fun opportunity to meet the members of the STA 199 teaching time. The only rule is these canโ€™t turn into office hours!

Tea with a TA counts as a statistics experience.

  • Matty Pahren, October 2 1p - 2p
    • Click here to sign up. Zoom details will be emailed before the event.
  • Ezinne Nwankwo, October 8, 2:30p - 3:30p
    • Click here to sign up. Zoom details will be emailed before the event.

Questions from video?

Recap of CLT & Normal distribution

Getting started

Clone the ae-13 repo and start a new project in RStudio.

AE 13: Bone density

Suppose the mean bone density for a 65-year old woman is normally distributed with mean 809 mg/cm3 and standard deviation of 140 mg/cm3 (these are actually pretty accurate numbers).

Exercise 1

What bone densities correspond to the 5th, 10th, 50th, and 99th percentiles of this distribution?

Exercise 2

The densities of three woods are below:

  • Plywood: 540 mg/cubic centimeter
  • Pine: 600 mg/cubic centimeter
  • Mahogany: 710 mg/cubic centimeter

What is the probability that a random 65-year old woman has bones less dense than each of these three woods?

Exercise 3

What is the probability that, for a group of 10 randomly sampled 65-year old women, the mean bone density of the group is less dense than these three woods?

Exercise 4

Explain the differences between your answers in Exercise 2 and 3.