Construct a hanging rootogram from the data of Problem 48 in order to compare the observed distribution to an exponential distribution.
The exponential distribution is widely used in studies of reliability as a model for lifetimes, largely because of its mathematical simplicity. Barlow, bland, and Freeman (1984) analyzed data on the strength of Kevlar 49/epoxy, a material used in the space shuttle. The times to failure (in hours) of 76 strands tested at a stress level of 90% are given in the following table.
a Construct a probability plot of the data against the quantiles of an exponential distribution to assess qualitatively whether the exponential is a reasonable model. Can you explain the peculiar appearance of the plot?
b Compare the data to the exponential distribution by means of a hanging rootogram.