- Announcements:
- Your graded assignment on Geometry is being returned today.
- Part I: #14 -- folks, the answer is in the back of the
book! But please put it into your own words....
- Part II: #15
- Someone asked to see #2, p. 244
- Someone asked to see #4, p. 284
- For next time: read section 7.5: Collecting Data Rather than Dust (this is the "lying" part!;)
- Section 7.6: What the Average American Has
(or had, in
1993)
- Section 7.6: Mindscapes #5, 6, 9, 23, 26 (type up #22)
Due Monday, 10/27
- Some statistics:
- The average American has one testicle and one
ovary.
- The average income for a Lakeside School
graduate was $2.5 million (in 1997)
- What's in a mean?
- Let's try a different measure of "central tendency":
The median American has no testicals and two
ovaries.
- What's in a measure of center?
- Visual display of data:
- Heights of our class
- Constructing a histogram (using heights)
- Interpreting measures of central tendency from the histogram
- Heights
of people tend to be normally distributed (if
distinguished by sex); otherwise, if the sexes are
combined, you might expect a bi-modal
distribution
- Normal distributions arise quite naturally (hexstat)
- Cars
- Let's generate our own "normal data",
- What's not in a mean or median? Spread, or
variation
- How do we quantify variation?
- "The mean difference from the mean" is one way....
- Standard deviation is another. This is a
"typical deviation" from the mean, or a "standard
deviation"...
In any event, these measures help us to appreciate
about by how much an individual measurement typically
varies from the mean.
- Interpreting measures of variation (from the histogram)
Website maintained by Andy Long.
Comments appreciated.
