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Survival analysis. And the legend of the exploding barbeque…. The problem. Barbeques, while tasty, use gas bottles. From time to time, and with no warning, these bottles randomly explode. . This tends to put a dampner on parties. The problem.
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Survival analysis And the legend of the exploding barbeque…..
The problem • Barbeques, while tasty, use gas bottles. • From time to time, and with no warning, these bottles randomly explode. • This tends to put a dampner on parties.
The problem • How to design an experiment to test the exploda-bility of 2 BBQs? • Could get 20 of each BBQ, use them for 40 days, look at number of days till explosion. • How do we analyse these data? • What about ones that didn’t explode?
The problem • We could just remove the data that didn’t explode • But they’re an important part of the analysis • Need to instead work out a hazard function, the chance of each BBQ type exploding on each day. • E.g. we go back to our data, and find the Red Neck Roaster has a 1% chance of exploding per day • For The T-Bone terminator, it’s 0.1%
Results.. Redneck roaster T-Bone Terminator
Survival analysis • Hazard function forms the basis of survival analysis • Used for any “time to event” data Everything eventually dies/fails Looking for differences in rate