Data Basics & Sampling Strategies

Question 1

In a chart, what are in the rows?

Answer 1

Samples

Question 2

In a chart, what are in the columns?

Answer 2

Variables

Question 3

What are the different types of variables?

Answer 3

Numerical and Categorical

Question 4

What are the different types of numerical variables?

Answer 4

Continuous and Discrete

Question 5

What are the different types of categorical variables?

Answer 5

Regular (nominal) and Ordinal

Question 6

What is a continuous numerical variable?

Answer 6

Beyond whole numbers (includes fractions and decimals)

Question 7

What is a discrete numerical variable?

Answer 7

Integers (whole numbers only)

Question 8

What is a regular (nominal) categorical variable?

Answer 8

Random/no natural order to the categories

Question 9

What is a ordinal categorical variable?

Answer 9

There’s a natural order to the categories

Question 10

What is an explanatory variable?

Answer 10

Variable used to explain other variable- effects the response variable

Question 11

What is a response variable?

Answer 11

The variable being tested

Question 12

What are the different data collection types?

Answer 12

Observational and Experimental

Question 13

What is an observational data collection?

Answer 13

Collecting data without interfering; observing the outcomes naturally

Question 14

What is an experimental data collection?

Answer 14

Assigning subject to different types of treatments and seeing what happens

Question 15

What is a sample group?

Answer 15

A subset of the population

Question 16

What are the different types of sampling bias?

Answer 16

Non-response, Voluntary, and Convenience Response

Question 17

What is non-response bias?

Answer 17

Only a small fraction of people respond

Question 18

What is voluntary response bias?

Answer 18

People choose to participate; usually people who do have very strong opinions on the topic

Question 19

What is convenience response bias?

Answer 19

Easily accessible people to ask

Question 20

What are the different types of sample groups?

Answer 20

Census, Explanatory Analysis, and Inference

Question 21

What is a census?

Answer 21

The entire population- hard because it costs a lot, is expensive, and population is constantly changing

Question 22

What is an inference sample type?

Answer 22

Sample that can be a representative of the entire population

Question 23

What is necessary for obtaining a good sample?

Answer 23

Large sample size and Randomization

Question 24

What are the different types of randomization?

Answer 24

Simple, Stratified, Cluster, and Multi-Stage Cluster

Question 25

What is simple randomization?

Answer 25

Randomly pick from the population; no additional information given

Question 26

What is stratified randomization?

Answer 26

Random sample within different subgroups; equal representation within the subgroups; Not everyone's "answers" will be used in the data

Question 27

What is a strata?

Answer 27

The different subgroups within a stratified randomization

Question 28

What is cluster randomization?

Answer 28

randomly sample from randomly assigned groups; nonhomogeneous; everyone within selected groups is included

Question 29

What is multi-stage cluster randomization?

Answer 29

Randomly assigned groups and then random sampling within the groups

Question 30

What is a parameter?

Answer 30

A characteristic of the population that you are wanting to "test"

Question 31

What is a statistic?

Answer 31

Characteristic of the sample- statistics approximate the parameter

Question 32

What is a control?

Answer 32

control group for the potential effect of variables other than the one's being studied

Question 33

What does randomize mean in an experimental study?

Answer 33

randomly assign subjects to treatment and randomly sample from the population

Question 34

What does replicate mean in an experimental study?

Answer 34

Be able to replicate entire study or collect a sufficiently large sample

Question 35

What is a block?

Answer 35

Similar to stratified groups in an observational study; variable known/suspected to affect response variable Ex: age or gender - randomize cases within each block to treatment group

Question 36

What is an explanatory variable?

Answer 36

affect response variable, not included in analysis

Question 37

What is a placebo?

Answer 37

A fake treatment used for the control group

Question 38

What is the placebo effect?

Answer 38

showing improvement because they believe they are receiving the treatment

Question 39

What is blinding?

Answer 39

experimental units do not know whether they are in control or treatment group

Question 40

What is double-blind?

Answer 40

Both the experimental units and researches do not know who is in control or treatment group