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What is Kaplan meier methods is used for - and explain in detail?
Ans. is 'a' i.e., Survival o The Kaplan-Meier estimator (also known as the product limit estimator) estimates the survival function from life-time data. In medical research, it might be used to measure the fraction of patients living for a ceain amount of time after treatment. o A plot of the Kaplan-Meier estimate of the survival function is a series of horizontal steps of declining magnitude which, when a large enough sample is taken, approaches the true survival function for that population. The value of the survival function between successive distinct sampled observations is assumed to be constant. o An impoant advantages of the Kaplan-Meier curve is that the method can take into account "censored" data ? losses from the sample before the final outcome is observed (for instance, if a patient withdraws from a study).