Exercise 16 “Old Faithful”

Refer to the sample data from the given exercises in Section 13-2 on page 611. Use the Wilcoxon signed-ranks test for the claim about the median of a population.

Data From Exercise 16 Section 13-2:

Refer to Data Set 23 “Old Faithful” in Appendix B for the time intervals before eruptions of the Old Faithful geyser. Use a 0.05 significance level to test the claim that those times are from a population with a median of 90 minutes. 

Refer to the indicated data set in Appendix B and use the sign test for the claim about the median of a population.

Data Set 23: Old Faithful 

Data are from 250 eruptions (first five rows shown here) of the Old Faithful geyser in Yellowstone National Park. INT BEFORE is the time interval (min) before the eruption, DURATION is the time (sec) of the eruption, INT AFTER is the time interval (min) after the eruption, HEIGHT (ft) is the height of the eruption, and PRED ERROR is the error (min) of the predicted time of eruption. Based on data from the Geyser Observation and Study Association.