Construct a scatterplot from a data table

Construct a scatterplot

A scatterplot represents paired numerical data. Identify the explanatory and response variables, use the explanatory variable horizontally, and plot one ordered pair for each case

1. Identify the variable roles The explanatory variable is used to help predict the response variable \(\displaystyle \text{EV}\to\text{RV}\)
2. Use the axis convention Put the explanatory variable on the horizontal axis and the response variable on the vertical axis \(\displaystyle x=\text{EV},\quad y=\text{RV}\)
3. Keep each pair together Plot one point for each case using the ordered pair (EV value, RV value) \(\displaystyle (x_i,y_i)=(\text{EV value},\text{RV value})\)
4. Label and scale both axes Name both variables with their units and choose scales that cover every value in the table \(\displaystyle x_{\min}\le x\le x_{\max},\quad y_{\min}\le y\le y_{\max}\)

Worked example

An investigation uses distance cycled to help predict energy used for a ride. One row of its table gives 24 km and 156 kJ. Construct the coordinate for that case in horizontal-axis, vertical-axis order

1. \(\displaystyle \text{distance cycled}=\text{EV},\quad\text{energy used}=\text{RV}\)The prediction question makes distance cycled the explanatory variable and energy used the response variable
2. \(\displaystyle x=24,\quad y=156\)Use the explanatory value first and the response value second
3. \(\displaystyle (\text{EV},\text{RV})=(24,156)\)The coordinate is (24, 156): 24 km horizontally and 156 kJ vertically

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