Question

Spot the flaw! Since 1953, when Tenzing Norgay and Edmund Hillary reached the summit of Mount Everest, many climbers have attempted to scale the world's highest mountain and its neighbor, named K2.Norgay and Hillary aided their climb by bringing supplemental oxygen in tanks, and some subsequent groups have attempted to out-do the originals by trying the ascent without supplemental oxygen. In fact, 159 teams comprising 1173 team members have attempted to climb either Everest or K2 between 1978 and 1999.The numbers of individuals who have either survived or died during those attempts (almost all fatalities occurred during descents) is given in the following table:

	Used supplemental O2	Did not use supp. O2	Row totals
Survived	1045	88	1133
Died	32	8	40
Column totals	32	96	1173

A chi-square independence (or contingency) test on these data calculated with one degree of freedom, which corresponds to P -value = 0.0055. The null hypothesis is that oxygen use has no effect on survivorship during these expeditions.

However, something is wrong with this analysis. What? Explain

Answer 1