Basics of Probability and Statistics Week 1 Challenge

Ans1. The Formula of variance differ between population and sample statistics because they serve distinct purpose and account for the difference in the data they represent

1-Population Variance- the population variance is used to measure the variability or spread of variables within the entire population

2-Sample Variance -The sample variance on the other hand is used to estimate the population variance when you have data from a subset of the population

The reason for the difference is to account for the fact that when you calculate the sample variance we estimate the population variance based on the sample of data by dividing n-1 instead of n we introduce a correlation factor

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Ans2.

Cluster sampling -The sampling is done on a population of clusters therefore cluster/group is considered a sampling unit

stratified Sampling- Stratified sampling elements within each stratum are sampled, we select a random sample in each stratum

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Ans3.The Number of differences in sample sizes n that be selected from a finite population of size N is Ncn

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Ans4.

1st Drawn 1/13

2nd Drawn 3/51=1/17

Both occur

1/13*1/17=1/221

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ans5.

Probabilty=6/36=1/6

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Ans6 Not Understand