Week 5-6 Flashcards
- What is the equation used for “Ordered without replacement”?
- How many distinct samples can you get when you select a sample size of 2, ordered and without replacement from a population of 3?
- check 5.1
* 6
- What is the equation used for “Ordered with replacement”?
- How many distinct samples can you get when you select a sample size of 2, ordered and with replacement from a population of 3?
- check 5.2
* 9
- What is the equation used for “Unordered with replacement”?
- How many distinct samples can you get when you select a sample size of 2, unordered and with replacement from a population of 3?
- check 5.3
* 6
Define Simple Random Sampling (SRS)
Selection of a sample that contains a n number of sampling units from a population of N number of sampling units in a way that every N(C)n distinct samples has an equal probability of being selected.
Show that the number of distinct samples that can be selected in a SRS, unordered and without replacement is 1/N(C)n (***probability?)
- check 6.1
An ordered random sample of size n is selected from a population size of N with replacement, what is the probability of getting the sample?
1/N^n
- What is the equation for the Sample Variance?
* Prove the equation
check 6.2
What are the 4 main characteristics of a population?
1) Mean
2) Total
3) Ratio
4) Proportion
What is an “unbiased estimator”?
check 6.2
Show that sample mean is an unbiased estimator for population mean
check 6.2
Show that s^2 is an unbiased estimator for the sd^2 when sampling is simple random sample and with replacement
check 6.2
Show that s2 is an unbiased estimator for the S^2 when sampling is simple random sample and without replacement.
check 6.2
What is the variance of the sample mean with replacement?
check 6.2
