Example 1 from Algebra and Trigonometry, 4.3 Fitting Linear Models to Data

Using a Scatter Plot to Investigate Cricket Chirps

Table 1 shows the number of cricket chirps in 15 seconds, for several different air temperatures, in degrees Fahrenheit5. Plot this data, and determine whether the data appears to be linearly related.

Selected data from http://classic.globe.gov/fsl/scientistsblog/2007/10/. Retrieved Aug 3, 2010

Chirps	44	35	20.4	33	31	35	18.5	37	26
Temperature	80.5	70.5	57	66	68	72	52	73.5	53

Table 1 Cricket Chirps vs Air Temperature

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
Plotting this data, as depicted in Figure 2 suggests that there may be a trend. We can see from the trend in the data that the number of chirps increases as the temperature increases. The trend appears to be roughly linear, though certainly not perfectly so.

Figure 2

How did it go?

Solution

Solution