Statistics Unit 4 - Designing Studies

Question 1

Census

Answer 1

Collects data from every individual in the population

Question 2

Population

Answer 2

The entire group of individuals you want information about

Question 3

Sample

Answer 3

A subset of the population; the
group from which we actually
collect data

Question 4

Stratified Random Sampling

Answer 4

Population is divided into groups, then a random sample is selected from each group

Question 5

Cluster Sampling

Answer 5

Population is classified into groups, then a random sample of the clusters is chosen

Question 6

Bias

Answer 6

When some outcomes are favored over others

Question 7

Undercoverage

Answer 7

When some members of the population cannot be chosen

Question 8

Nonresponse

Answer 8

When people can’t be contacted or refuse to participate

Question 9

Response

Answer 9

When people give false answers

Question 10

Lurking Variable

Answer 10

Influences both the explanatory and response variables

Question 11

Confounding

Answer 11

When two variables are associated in such a way that their effects on a response variable cannot be distinguished from each other

Question 12

Statistically Significant

Answer 12

An observed effect so large that it would rarely occur by chance

Question 13

4 Principles

Answer 13

Comparison - Compare two or more treatments
Control - Keep as man variables as possible the same for all treatment groups
Replication - Use enough subjects to determine differences in treatments
Randomization - Subjects should be randomly assigned to treatments

Question 14

Inference about cause and effect

Answer 14

Can be made when individuals are randomly assigned to treatment groups

Question 15

Data ethics

Answer 15

All studies are review in advance by the board, individuals give informed (written) consent, and individual data is confidential