Logarithmic Models

1 Find the definition of g(r). What does this function do?

2 Find the Contract for build-column on the Contracts Page.

3 At the end of the program, you’ll find this code:

4 Click "Run", and evaluate countries-transformed in the Interactions Area on the right to test it out!

a. What is different about this Table? Hint: Find the last column!

b. Where did the column on the right come from?

5 Use this new table to make an lr-plot comparing log(pc-gdp) and median-lifespan, with country as the label. Record the regression line and S value below:

y = slope x + vertical shift S:

6 Use the model settings of the linear model you just made to complete the logarithmic model below:

logarithmic3(x) = log coefficient (a) log₁₀(x) + vertical shift (k) fun logarithmic3(x): ( * log(x)) + end

7 Let’s interpret this model:

8 Add the definition of logarithmic3 to your starter file. Use fit-model to calculate the S-value and complete the table below:

9 Compare the two smallest S values using percent change. $$\displaystyle \frac{  \text{Difference}   \text{between}   \text{the}   \text{S-values} } {\text{S-value}   \text{for}   \text{second}   \text{best}   \text{model}} \times 100   =  $$$$\displaystyle \frac{\qquad}{\qquad}$$

Predictions made with the logarithmic model are expected to have percent more / less error than predictions made with the model!