Main goal: Comparing Distributions

Sub-goal: When you add more data, you get closer to the population

· Preliminary-motivation

· Exploration

· Discussion Work

· Discussion 3

Purpose/Question: What is one best representative sampling of population. What is the most representative sector of nine sectors that represent this field?

Thoughts:

When does question of fairness, proportional reasoning come in? Do kids already realize this? Exploration assumes the need to normalization so what needs to be covered and when? Topic of metric- better to discuss in small groups

Discussion:

Given 3 distributions of broccoli survey. Compare: Class 1 and 2

Class 2 and 3

Class 1 and 3

Distribution-each sheet is a distribution. Each group comes up with its own method of answering question: How different are these two distributions? Each group will come up with the metrics. What will they do? They may add absolute differences; they may add or subtract. Each group presents their method. This will take one class period.

Note: Joanna-doing absolute values now

Next discussion:

Now, these classes were the same size. What do you do if you have different sizes?

One class, 3 kids like broccoli, another class 6 kids like broccoli. Which class likes broccoli more?

In one class: 3 like, 5 dislike, 2 don’t care.
In another class: 6 like, 10 dislike, 4 don’t care.

Will kids compare using fractions?

You’re telling me kids like and dislike broccoli is the same?

Class 1 - going to change this to percentage

Class 2 - going to change this to percentages

And these percentages will be the same.

When students study distributions of their own fields, they’ll know that they must do their transparencies in percentages.