4. Experiments

Question 1

What is observation in research?

Answer 1

Registering an empirical phenomenon.

Question 2

What does manipulation refer to in a study?

Answer 2

Changing a variable in a study.

Question 3

What is an intervention?

Answer 3

Changing an independent variable.

Question 4

What is control in research?

Answer 4

Reducing the influence of disturbing factors/variables from influencing the outcome.

Question 5

What are independent variables?

Answer 5

Variables that are hypothesized to affect the dependent variable.

Question 6

What are dependent variables?

Answer 6

The variable that changes depending on the changes of the independent variable.

Question 7

What is the method of difference?

Answer 7

By creating two identical groups, and making an intervention on only one of them, the causal effect of that intervention can be studied.

Question 8

What defines an experiment?

Answer 8

An observational process characterized by control of the background factors, intervention on the real target variable, and observation of the differences caused by this intervention.

Question 9

What is a control group?

Answer 9

A contrast class that is not subjected to the intervention, but is similar to the treatment group in all other relevant aspects.

Question 10

What is a treatment group?

Answer 10

A class that is subjected to the intervention.

Question 11

What is an observational study?

Answer 11

An observational process characterized by control of the background factors and observation of an outcome, lacking an intervention.

Question 12

What is a natural experiment?

Answer 12

An observational study where circumstances are organized as if there had been manipulation for intervention and control, but no manipulation is in fact done.

Question 13

What is a field experiment?

Answer 13

An experiment where there is manipulation for intervention, but where several background variables are not controlled.

Question 14

What is a laboratory experiment?

Answer 14

An experiment where there is manipulation for intervention and where all or most relevant variables are controlled.

Question 15

What is a simulation experiment?

Answer 15

A model study where the model is created to mimic an experiment, but where the variables that are intervened on are only represented.

Question 16

What is internal validity?

Answer 16

An inference in a scientific study is internally valid if the relation between the studied factor and observed effect is indeed true and not confounded by uncontrolled background factors.

Question 17

What is external validity?

Answer 17

An inference from an experimental system to a different target of interest is externally valid if the conclusion holds for both the system and the target.

Question 18

What is confirmation bias?

Answer 18

The observation is registered incorrectly due to psychological properties of the observer.

Question 19

What is selection bias?

Answer 19

A factor influences the selection of the sample or the division into test and control group, which was not aimed to create.

Question 20

What is the observer effect?

Answer 20

The act of observation changes what is observed.

Question 21

What is the placebo effect?

Answer 21

The therapeutic effect that an inert substance or treatment has on a patient.

Question 22

What is repetition in research?

Answer 22

Performing a study again, exactly following the description of the original study.

Question 23

What is reproduction in research?

Answer 23

Repeating a study and obtaining the same result as in the original study.

Question 24

What is replication in research?

Answer 24

Performing a variation of a study with the intention to achieve the same result, where some aspect of the study has been changed.

Question 25

What is constancy in research?

Answer 25

Holding background factors constant between test and control group or between trials in a study.

Question 26

What is elimination in research?

Answer 26

Removing the influence of a background factor.

Question 27

What is blinding in research?

Answer 27

Eliminating observer effects through limiting information about the study to participants or observers.

Question 28

What is single blinding?

Answer 28

Blinding the participants in a study, for instance about whether they are in the test or control group.

Question 29

What is experimenter blinding?

Answer 29

Blinding the observer in a study, for instance about which subjects are in the test and control group.

Question 30

What is double blinding?

Answer 30

A study is double blind if both subject blinding and experimenter blinding are implemented.

Question 31

What is separation in research?

Answer 31

Registering the effect of a background variable.

Question 32

What is randomization?

Answer 32

Using a random process to divide into test and control.

Question 33

What is random sampling?

Answer 33

Using a random process to collect a sample from the population.

Question 34

What are evidential hierarchies?

Answer 34

A ranking of types of evidence based on the processes that produced this evidence.

Question 35

What is data stratification?

Answer 35

Dividing a sample into categories based on specific properties before randomizing.

Question 36

What is a known factor?

Answer 36

A factor which you are aware of constitutes a relevant background factor.

Question 37

What is an unknown factor?

Answer 37

A factor which is a relevant background factor, but which you are unaware of.