Day 11: STA205 - Introduction to Statistical Methods

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• Announcements:
  • Your quiz is returned.
    1. Population:
    2. Sampling Frame:
    3. $H_0: p=____$; $H_a: p<____$
    4. random sample, $np>10$, $n(1-p)>10$.

  • Your normal plotters are here! Thanks to Danny....

  • Your first exam is coming up next week, Thursday -- it will cover through Packet 5 (which we begin today)

• Today we complete Packet 04 (Hypothesis Test for p).

  • Then we'll begin Packet 5, which has two major objectives:
    1. estimate parameter $p$ using statistic $\hat{p}$, with given confidence, and
    2. discover the sample size needed to estimate $p$ with given confidence.

• Links:
  • The Standard Normal Table of probabilities.

  • Statcrunch instructions:
    • Load the Stop and Frisk Data for packet 2. Load it by "WWW address", and make sure to set the delimiter to "comma" (because this is a "csv" (comma-separated values) file.
    • Once the data is loaded, click on "Graph" or "Table".
    • Alternatively, you may want to join my "group" on Statcrunch. That way you can access the data more quickly. It's Sta205-Long, if you want to add yourself into that group.
    • For the IMath homework, you'll need the Bipolar Depression Study data. Same thing: Load it by "WWW address", and make sure to set the delimiter to "comma" (because this is a "csv" (comma-separated values) file (or get it from the group).

• Today, if we have a little more time, we will startPacket 5), which has two major objectives:
  1. estimate parameter $p$ using statistic $\hat{p}$, with given confidence, and
  2. discover the sample size needed to estimate $p$ with given confidence.

  Let's remind ourselves about the distribution of $\hat{p}$:

  
  

  Now in this case we don't have $p$. We want to find $p$. So how do we proceed? That's the subject of this packet.

• Links:
  • Please watch Brooke's Hypothesis test for the proportion at some point.
  • The Standard Normal Table of probabilities.
  • Interview with Richard Feynman