Unit 3: Collecting Data

Question 2

experimental unit

Answer 2

individuals or people in the study

Question 3

explanatory variable

Answer 3

The variable that the researchers manipulate for observation
(think: independent variable!)

Question 4

response variable

Answer 4

The variable being measured or observed in response to changes made to explanatory variables
(think: dependent variable!)

Question 5

4 principles to any good experiment

Answer 5

1. Comparison
2. Random assignments
3. Direct Control of potential confounding variables (external influences)
4. Replication

Question 6

Comparison

Answer 6

At the very minimum, an experiment must have 2 treatments

Question 7

Random Assignments

Answer 7

Which experimental units receive what treatment must be random. This takes out most potential confounding variables.

Question 8

Direct Control

Answer 8

Ensuring that confounding variables are the same throughout the samples

Question 9

Replication

Answer 9

Having as many subjects in the treatment groups as possible

Question 10

Three experimental designs

Answer 10

1. Completely random
2. Randomized block design
3. Matched pair

Question 11

Completely random design

Answer 11

Between two groups, everything must be the same except the variable you’re changing

Question 12

Randomized block design

Answer 12

Separating groups based on certain attributes
(different concept from stratified sampling!)

Question 13

Matched pair design

Answer 13

Pairs of two individuals with similar attributes and only one individual of the pair gets the experiment

Question 14

statistical inference

Answer 14

using data from a sample to make a judgement

Question 15

statistically significant results

Answer 15

statistically significan suggests that the difference or relationship found in the data reflects a true pattern rather than random variation