Exercise: survival after retirement, suggested answer 2

Graph with 'Probability of survival' on vertical axis, 'Survival time (years)' on horizontal.  Two curved lines from survival time = 0, probability = 1.0, going down more and more steeply to time = 20, probablity = 0.38 and probability = 0.30 approximately.  Upper line is 'Retired at 65', lower line is 'Retired at 55'.

2. Why do you think the curves become steadily steeper as survival increases?

Suggested answer

These survival curves cover ages 65 to 85, a period when mortality rates get bigger as age increases. So the hazard is getting bigger all the time and the proportion dying in each year is getting bigger all the time. Hence the curves get steeper.

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