Basics of Probability and Statistics Week 1 Challenge

1. When we calculate population variance, we divide by N (the population size). When we calculate sample variance, we divide by n-1 (the sample size – 1).

2. Cluster sampling divides a population into groups, then includes all members of some randomly chosen groups.

Stratified sampling divides a population into groups, then includes some members of all of the groups.

3. The size of the sample to be taken is equal to the size of the population. This means that the number of different random samples that can be taken is 1

4. 4/52*3/51=12/2652

= 1/221

5 P(N, N) = 1/6

6. Variance helps to find the distribution of data in a population from a mean, and standard deviation also helps to know the distribution of data in population, but standard deviation gives more clarity about the deviation of data from a mean.