(This measurement is helpful in diagnosing various
lung disorders.) The two instruments considered
were a Wright peak flow meter and a mini-Wright
peak flow meter. Seventeen people participated in
the study, and for each person air flow was measured
once using the Wright meter and once using the
mini-Wright meter.
Subject
Mini-
Wright
Wright
Meter
Meter
Subject
Mini-
Wright
Wright
Meter
Meter
512
494
10
445
433
430
395
432
417
520
516
12
626
656
428
434
13
260
267
500
476
14
477
478
600
557
15
259
178
364
413
16
350
423
380
442
451
427
658
650
a. Suppose that the Wright meter is considered
to provide a better measure of air flow, but the
mini-Wright meter is easier to transport and to
use. If the two types of meters produce different
readings but there is a strong relationship between
the readings, it would be possible to use a reading
from the mini-Wright meter to predict the reading
that the larger Wright meter would have given.
Use the given data to find an equation to predict
Wright meter reading using a reading from the
mini-Wright meter. (Hint: See Example 5.4.)
b. What would you predict for the Wright meter
reading of a person whose mini-Wright meter
reading was 500?
c. What would you predict for the Wright meter
reading of a person whose mini-Wright meter
reading was 300? (Hint: See discussion of
extrapolation that follows Example 5.4.)