Expand Your Knowledge: Logarithmic Transformations, Exponential Growth Model Let x 5 day of observation and y 5 number of locusts per square meter during a locust infestation in a region of North Africa.

x 2 3 5 8 10 y 2 3 12 125 630

(a) Draw a scatter diagram of the (x, y) data pairs. Do you think a straight line will be a good fi t to these data? Do the y values almost seem to explode as time goes on?

(b) Now consider a transformation y 5 log y. We are using common logarithms of base