Midterm Review

Question 1

Population of Interest

Answer 1

Collection of elements about which we wish to study

Water Problem: All households that consume water in city

Question 2

Sampling Unit

Answer 2

Cellection of elements from population that we will use as sample to cover entire population
Water Problem: Household, City Block

Question 3

Sampling Frame

Answer 3

From where we will choose the sampling units from

Water Problem: Phone Book

Question 4

Simple Random Sampling

Answer 4

Every sample size n has same chance of being selected. Thus every sampling unit has the same chance of being selected

Question 5

Stratified Random Sample

Answer 5

Define non-overlapping samples and from within each non-overlapping samples take a simple random sample

Question 6

Way to minimize errors of estimation

Answer 6

Increase sample size

Question 7

Error of Observations

Answer 7

Non-Response, Coverage Bias

Question 8

Ways to minimize nonresponse in a survey

Answer 8

Offer incentives, Notify potential respondents in advance

Question 9

Properties of a good estimator

Answer 9

Small variance, and it is unbiased

Question 10

Sample Variance

Answer 10

s^2

Question 11

Confidence Interval population proportion

Answer 11

p^ +/- 2* Square Root of (Variance for SRS)

p^ is given sample proportion or if not given then p^ is .5

Question 12

Bound

Answer 12

2*Square Root of (Variance for SRS)

Question 13

p^ value for population total

Answer 13

x bar times N