---
title: "S4R: Class 26 Simple linear regression, logarithm transformation"
author: "Your Name Here"
date: "`r format(Sys.time(), '%B %d, %Y')`"
output:
html_document:
toc: true
---
# Rubric
1. With your previous (or new) bivariate scatter plot, add a regression line.
* (1 p) plot with regression line,
* (1 p) label axes and title.
2. Try plotting the data on a logarithmic scale ($x$-only, $y$-only, both).
What happened to your data when you transformed it?
* (1 p) At least one logarithmic relationship is plotted, and indicate why you chose this transformation.
* (1 p) Describe what happened to the relationship (compare original scale to transformed scale).
3. Does your relationship benefit from a logarithmic transformation?
* (1 p) Say whether the relationship became more linear with reference to your plots.
4. Use `lm()` to fit the linear regression and interpret slope and $R^2$ (R-squared) values.
* (1 p) lm summary table is presented,
* (2 p) slope is interpreted with respect to the increase in the $y$ variables for each unit increase of the $x$ variable
in the context of the variables in the plot,
* (1 p) $R^2$ is interpretted in a sentence.
5. (1 p) Interpret the intercept.
Does it make sense in the context of your study?
Can the $x$-variable be centered to improve the intercept's interpretation.