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Topic: Re: suggestion needed
Replies: 0

 Larry Peterson Posts: 14 Registered: 12/6/04
Re: suggestion needed
Posted: Sep 30, 1996 2:22 PM

An very interesting activity is to have students measure the
circumference of their wrists and the circumference of their necks.
Make a scatter plot of these values. The students can quickly see a
strong, positive, association between the two. Have them draw a
"typical" line that gives the best fit to the relationship. Have
teams of students pick two random data points that seem to be on this line and compute the slope and equation of the line
using traditional algebra techniques (y = ax + b). Compare the equations and see
how close they are.

Then use technology to find the actual regression line. See which
students came the closest. Use their line and the actual regression
to compute y-hat and the correlation coefficient along with
r-squared. This helps them to see the meaning of the line with best
fit and the best correlation coefficient.

Now they are able to gain an physical nderstanding of the slope in
this problem. As wrist size increases by 1 cm, the neck size
increases by "a" cm (where a is the slope of the line). Choose a few
students at random and see how well the equation predicts their neck
size. Try the prediction on a few people who were not part of the
original sample (sucj as the visitors) and see how accurately the
equation works for them. Have the students brainstorm as to reasons
why the other people do or do not fit the predicted equation.

Acitivities that involve the students in active learning do the best
job in helping them understand the concepts not the just the
mechanics. It always impresses visitors to see students working
excitedly on math. Involving the visitors insures their atttention
to the lesson as well.

Good luck,
Larry

Larry Peterson
Bonneville High School Home
251 E Laker Way 4470 S 1650 W
Ogden, Utah 84405 Roy, Utah 84067
801-476-5808 801-731-4267