Audiometry Use the right ear threshold measurements and the corresponding left ear threshold measurements from Data Set 4 “Audiometry” in Appendix B. What is the best predicted threshold measurement for the left ear given a measurement of 20 for the right ear? Large Data Sets. Exercises 25–32 use the same Appendix B data sets as Exercises 25–32 in Section 10-1. In each case, find the regression equation, letting the first variable be the predictor (x) variable. Find the indicated predicted values following the prediction procedure summarized in Figure 10-5 on page 466.