Example of a simple scatterplot
main topics     interpreting results      session command     see also 

You are interested in how well your company's camera batteries are meeting customers' needs. Market research shows that customers become annoyed if they have to wait longer than 5.25 seconds between flashes.

You collect a sample of batteries that have been in use for varying amounts of time and measure the voltage remaining in each battery immediately after a flash (VoltsAfter), as well as the length of time required for the battery to be able to flash again (flash recovery time, FlashRecov). Create a scatterplot to examine the results. Include a reference line at the critical flash recovery time of 5.25 seconds.

1    Open the worksheet BATTERIES.MTW.

2    Choose Graph > Scatterplot.

3    Choose Simple, then click OK.

4    Under Y variables, enter FlashRecov. Under X variables, enter VoltsAfter.

5    Click Scale, then click the Reference Lines tab.

6    In Show reference lines at Y values, type 5.25. Click OK in each dialog box.

Graph window output

Interpreting the results

As expected, the lower the voltage in a battery after a flash, the longer the flash recovery time tends to be.

The reference line helps to illustrate that there were many flash recovery times greater than 5.25 seconds.