Day 2: STA205 - Introduction to Statistical Methods

Last time

Next time

• Announcements:
  • Anyone new here? You'll have some stuff to fill out...

  • Reminder: stash your rectangles.

  • Many apologies for the screw-up in the bookstores. Seems to happen too often. I spoke to our administrative assistant, and she said that it's the bookstores' bad: our class was supposed to require only StatCrunch. So if you bought your MyStatLab from either bookstore, you should be able to return it easily. Let me know if you have any problems doing so.

  • Registering for IMath:
    • In a browser, go to imath.nku.edu
    • In the log-in box on the right side of the screen, click Register as a new student.
    • Enter a username, password, name, and email address.
    • In the Course ID box, enter 270.
    • In the Enrollment Key box, enter 205s17
    • Click Sign Up.

  • Your first homework on IMath:
    • By the end of today you'll be able to do the first four (at least) of the problems on your first homework set.
    • By next time, you should be able to finish it.
    • It's due next Friday (not this Friday).

  • We'll have our first quiz next Wednesday.
  • No class Monday! Happy MLK day....
  • Did everyone get their packet printed off? Because here we go!:)

• Today: the normal distribution
  • Last time we talked about how statistics and probability go together. We talked about different ways of thinking about statistics (descriptive and inferential), and about some aspects of probability (e.g. probability 0 means impossible; probability 1 means certain; probabilities are numbers between 0 and 1).

    We talked about "H bar" notation: things with bars over them are means.

    Any questions before we continue?

  • One more example, before we go on: Average ("mean") temperature in Cincinnati:
    
    1. What statistics are being shown in this graphic?
    2. How do we relate the statistics to probabilities?
    3. The high is forecast to be 61 degrees F on Thursday. How do you relate that to probabilities for this particular date?
    4. On Saturday, the high is forecast to be 39 degrees F. How do you relate that to probabilities for this particular date?

  • Our class heights:
    • Let's start by looking at them in reality (this will get our blood flowing!).
    • Let's take a look at them in StatCrunch
    • If we just google "distribution heights us males", we get some idea of how folks in the US "stack up". We can also observe the difference between men and women.
    • A nice summary, introducing the notion of the normal distribution.

• Let's take a look now at Packet 1: the normal distribution.
  • If you don't have your Packet 1, just take out some paper and make notes that you can use to transfer to your packet when you DO get it printed out.
  • We may need the Standard Normal Table of probabilities for some of our work today.