Open your copy of the State Demographics Starter File.

The al-ak Model

Type fit-model​(​states-table, "state", "pct-college-or-higher", "median-income", al-ak​) in the Interactions Area, then find the points representing AL and AK along the predictor line. Hint: You know their coordinates and they will help you know where to look!

1 What do you Notice?

2 What do you Wonder?

3 Find S in the upper left corner. What is the S value (the number after S)?

4 With median income ranging from lowest median income to highest median income, what does the S-value of the al-ak model tell us?

Comparing Models

5 Use fit-model to find the S-value for the mi-ca model.

6 Is the mi-ca model better or worse than the al-ak model?

7 How much more / less error do we expect in predictions made with the mi-ca model than predictions made with the al-ak model?

Percent Change   =   $$\displaystyle \frac{  \text{Difference}   \text{between}   \text{the}   \text{S-values} } {\text{S-value}   \text{for}   \text{al-ak}   \text{model}} \times 100   =  $$$$\displaystyle \frac{\qquad}{\qquad}$$ mi-ca model predictions are expected to have percent more / less error than al-ak model predictions!

A Model of Your Own

8 Identify two other states that you think would make a better model: and .

Add two new definitions for these states to your State Demographics Starter File.

9 Record the college-or-higher and median-income values for these states, as (x,y) pairs below:

(college-or-higher, median-income) (college-or-higher, median-income)

10 Derive your model and write it below (in both Function and Pyret notation), then fit the model and record the S-value:

other(x) = slope (m)x + y-intercept / vertical shift

fun other​(​x​): (​  ​* x​) +   end S:

11 Adjust the slope and y-intercept of your model to get the smallest S possible. Write the best model you find (and corresponding S) below:

fun best​(​x​): (​  ​* x​) +   end S:

12 How much more / less error do we expect in predictions made with your model than predictions made with the mi-ca model? %

These materials were developed partly through support of the National Science Foundation, (awards 1042210, 1535276, 1648684, 1738598, 2031479, and 1501927). CCbadge Bootstrap by the Bootstrap Community is licensed under a Creative Commons 4.0 Unported License. This license does not grant permission to run training or professional development. Offering training or professional development with materials substantially derived from Bootstrap must be approved in writing by a Bootstrap Director. Permissions beyond the scope of this license, such as to run training, may be available by contacting contact@BootstrapWorld.org.