Presentation 2 : Experimental Design

Question 1

Define confounding variables

Answer 1

Variables that can potentially distort the relationship between the IV and DV
-> contribute to bias

Question 2

Define Target Population

Answer 2

the group of people to which the findings of the study are expected to be generalized. A group of people who can represent an entire population

Question 3

Define generalize

Answer 3

a measure of how useful the results of a study are for a broader group of people or situations

Question 4

Define Random Sampling

Answer 4

The ideal approach to sampling the representative. Every member of the target population has an equal chance of becoming part of the sample.

Question 5

Define Stratified sampling

Answer 5

researcher chooses the characteristics of the target population wished to be studied then chooses the sample to best reflect those desired characteristics.

Question 6

Define Convenience (opportunity)
sampling

Answer 6

The researcher recruits participants that are most easily available.

Question 7

Define Self-selected sampling

Answer 7

The researcher recruiting volunteers.

Question 8

Define Experimental Design

Answer 8

The organization of groups and conditions in an experiment

Question 9

Define Independent measures design

Answer 9

involves randomly allocation (placement) of participants from you sample group into the experimental group and the control group. Then manipulate the experimental conditions and compare the dependent variable in the two groups.

Question 10

Define Matched pairs design

Answer 10

similar to independent measures, the researcher purposefully matches participants to form groups.

Question 11

Define Repeated measures design

Answer 11

method used when the goal is to compare conditions rather than groups of participants. The sample group of participants is exposed to two (or more) conditions, and the conditions are compared.

Question 12

Define Construct validity

Answer 12

characterizes the quality of operationalization. Remember operationalization is how a researcher applies a measurable quality to a behavior.

Question 13

Define Internal validity

Answer 13

characterizes the methodological quality of the experiment. Internal validity is high when confounding variables have been controlled and high certainty the IV caused the change in DV.

Question 14

Define External validity

Answer 14

characterizes how the results of the research can be generalized (related) back to the population as a whole

Question 15

Define Selection Bias

Answer 15

Occurs when groups are not equivalent from the start of the experiment. (IV)

Question 16

Define History Bias

Answer 16

When outside events happen to participants in the course of an experiment. (IV)

Question 17

Define Maturation Bias

Answer 17

During the experiment participants go through natural

development, such as fatigue or simply growth. (IV)

Question 18

Define Experiment bias

Answer 18

occurs when the experimenter influences the

results unintentionally. (IV)

Question 19

Define Testing effect

Answer 19

The first measurements of the DV may affect the

second (and other) measurements.

Question 20

Define Instrumentation

Answer 20

This effect occurs when the instrument measuring the DV changes slighting between measurements. Such as an observer measuring a behavior.

Question 21

Define Regression to the mean

Answer 21

This occurs when the resulting DV’s measurement is extreme (either too low or high).

Question 22

Define Experimental mortality

Answer 22

refers to the fact that some participants

leave or drop out from the experiment, especially if not random.

Question 23

Define Demand characteristics

Answer 23

this situation happens when participants understand the purpose of the experiment and change their behavior to fit the experiment.

Question 24

Define Quasi-experiments

Answer 24

“Quasi” is a prefix meaning “almost”. In these experiments the groups are not made randomly and are grouped based upon pre-existing differences such as age, gender, culture and/or occupation.

Question 25

Define Field experiments

Answer 25

Experiments that are conducted in real life settings. The researcher manipulates the IV, but the participants are in their natural setting.

Question 26

Define Natural Experiments

Answer 26

conducted in participants natural environment, but here the researcher has no control over the IV – the IV occurred naturally.