# Key vocab - Research Methods Flashcards

Null hypothesis

A prediction that what the experiments are changing (the independent
variable) will NOT change the results.

Alternative hypothesis

A prediction that what the experiments are changing (the independent
variable) WILL change the results.

Conditions

The groups of the independent variable in a study.

Independent variable

The thing in a study that is being changed.

Dependent variable

The thing in a study that is being measured.

Extraneous variable

Other variables in a study that might also be affecting the results.

Sampling

How participants are chosen from the target population to take part
in a study.

Random sampling

Participants are chosen randomly. Everyone has an equal chance of
being selected.

Opportunity sampling

Participants are people who happen to be available and willing to
take part.

Systematic sampling

Participants are chosen using an ordered system. E.g. every 10th name
on this list.

Stratified sampling

Participants are chosen to try and keep certain categories
representative. E.g. 50% biological male, 50% biological female.

Quantitative data

Numerical data.

Qualitative data

Descriptive data.

Correlation

The relationship between 2 variables.

Positive correlation

When one variable increases, so does the other. E.g. as temperature
increases, ice cream sales increase.

Negative correlation

When one variable increases, the other decreases. E.g. as time spent
on training increases, the athlete's 100m time decreases.

What correlation does this image show?

Positive correlation

What correlation does this image show?

Negative correlation

Primary source

The researcher collects data directly from the participant.

Secondary source

The researcher uses data that was created for something else e.g.
medical records or government statistics.

Order effects

If participants do more than one condition, then the condition they
do first may affect how they perform in the second.

Counterbalancing

In repeated measures design experiments, researchers split which

Standardised procedures

Researchers use these to try and make sure every participant has the
same experience.

Lab experiment

A research method with an artificial setting, and the IV is controlled.

Field experiment

A research method with a natural setting, but the IV is controlled.

Natural experiment

A research method with a natural setting, and a naturally-occurring IV.

Independent groups