3. Sampling Techniques

SOLVED: 3. Sampling with and without replacement Sampling with replacement: A box contains tickets marked 1 2 n . A ticket is drawn at random from the box. Then this ticket is replaced in the box and a second ticket is drawn at random: Find the probabilities of the following events: the first ticket drawn is number L and the second ticket is number 2; b) the numbers on the two tickets are consecutive integers, meaning the first number drawn is one less than the second number drawn: the second nu

SOLVED:Consider simple random sampling with replacement. a. Show that s^2=(1)/(n-1) ∑i=1^n(Xi-X̅)^2 is an unbiased estimate of σ^2 b. Is s an unbiased estimate of σ? c. Show that n^-1 s^2 is an unbiased estimate of σ(2)/(X) d. Show that n^-1 N^2 s^2 is an unbiased estimate of σT^2 e. Show that p̂(1-p̂) /(n-1) is an unbiased estimate of σp̂^2

Sampling Bias Definition, Types & Examples

Sampling and Sources of Bias

Data Collection - Sampling