Effect of Scale on a Scatter Diagram The initial visual impact of a scatter diagram depends on the scales used on the x and y axes. Consider the following data:

x 1 2 3 4 5 6 y 1 4 6 3 6 7

(a) Make a scatter diagram using the same scale on both the x and y axes (i.e., make sure the unit lengths on the two axes are equal).

(b) Make a scatter diagram using a scale on the y axis that is twice as long as that on the x axis.

(c) Make a scatter diagram using a scale on the y axis that is half as long as that on the x axis.

(d) On each of the three graphs, draw the straight line that you think best fits the data points. How do the slopes (or directions) of the three lines appear to change? Note: The actual slopes will be the same;

they just appear different because of the choice of scale factors.

AppendixLO1