research methods

Random sampling

When everyone in the target population has an equal chance being selected as a ppt

Systematic sampling

Selecting every nth person in the target population

Opportunity sampling

Research takes the opportunity to take anyone to be available at the time of the study

Volunteer sampling

Ppl in target population select themselves to be ppts

Stratified sampling

The ratio of the target population of categories then same ratio for sample (pie chart one)

Advantages of repeated measures

• no ppt variables

• Only need half as many ppts as other experimental designs

Disadvantage of repeated measures

order effects (practicing) so can’t use same stimulus material E.g. same crossword puzzle

What’s counterbalancing

Half the participants do condition A then B, and the other half do B then A. Each participant experiences all conditions in a forward and reverse order.

Advantages of independent groups

• Use exactly same stimulus material in the two condition

• Demand characteristics, practice effects and order effects less likely

Disadvantage of independent groups

Participant variables

Advantages of matched pairs design

• no ppt variables

• Use the same stimulus material

Disadvantage of matched pairs

Very time consuming to match ppt on variables, especially multiple variables

What makes an experiment reliable

If the same results can be given time after time

Difference between single and double blind control

Single blind control is when the ppt is told there is a fake aim of the study, double blind is when the investigator is not told of the aim so they can’t bias their behaviour

Advantages of lab

• highly controlled variables

• High in internal validity

Disadvantages of lab experiments

• lower ecological validity

• Risk of demand characteristics

Advantages of field

• high ecogological validity

• No risk of demand demand characteristic

Disadvantages of field

• harder to replicate as less controlled

• Lower in internal validity

Difference between natural and field experiment

Field purposefully manipulates the IV, natural has the IV naturally occurring

Advantages of natural

• high ecological validity

• No risk of demand characteristics

Disadvantages of natural

• low internal validity

• Impossible to replicate

What is a quasi experiment

Naturally occurring IV, DV can be measured in a lab

E.g. studying men and women in lab

Advantage of quasi

high ecological validity

Disadvantages of quasi

• Can’t randomly allocate so other participant variables may be acting

• Low ecological validity so hard to establish cause and effect

Acronym for ethical considerations

Can Do Can’t Do With Participants

C - Consent (informed)

D - Deception

C - confidentiality

D - Debrief (at end)

W - Withdrawal (right to)

P - Protection from harm

Advantage of correlation

Let’s us make predictions

Disadvantage of correlation

Doesn’t imply causation

Participant vs non-participant observation

Non-participant is when the researcher does not take part in the experiment, participant is when they do

Covert vs over experiment

Covert is when the ppts don’t know they’re being studied (informed consent issues - however if in public presumptive consent)

Overt is when they do know (validity issues)

Difference between naturalistic and controlled observations

Naturalistic observations record spontaneous behavior in real-world settings without interference. Controlled observations occur in structured environments (like a lab), where researchers manipulate variables and standardize procedures to isolate specific behaviors

Difference between time sampling and event sampling

Time sampling is recording behaviour for a fixed period of time at specific intervals

Event sampling is recording a complete event which is believed to be important each time it occurs

How to perform an observation

1. Decide what to observe

2. Choose behaviour categories

3. Carry out observation with either time or event sampling

4. Quantify data

Advantages of naturalistic observation

• High ecological validity

• Useful when behaviour cannot be recreated in a lab

Disadvantages of naturalistic observation

• little to no control of variables so cause and effect cannot be inferred

• May be observer bias

Advantages of controlled observations

• easily replicated

• Less time consuming than naturalistic as data is quantitative

Disadvantages of controlled observation

• observer bias

• Low ecological validity

Advantages of case studies

• provides rich data about specific issue

• Sometimes is the only method available to use

Disadvantages of case studies

• difficult to generalise

• Not replicable

What is a content analysis

Converting content into an objective measure

How to perform content analysis

1. Decide what content to analyse

2. Decide coding units

3. Carry it out

4. Quantify it

Advantages of content analysis

• no demand characteristics

• High ecological validity

Disadvantage of content analysis

researcher interprets things differently (investigator effect)

What are the two self report techniques

Questionnaires and interviews

Advantages of questionnaires

• versatility

• Can produce a larger amount of info and easy to analyse (quantify)

Disadvantages of questionnaires

• social desirability bias

• Structured = lack of freedom, unstructured = difficult to analyse

Advantages of interviews

• used to explore complex issues

• Allows researchers to gain subjective meaning

Disadvantages of interviews

• interviewees may struggle to put thoughts into words

• Appearance and behaviour of interviewer may effect interviewee

If a normal distribution curve is positively skewed this means its too difficult or too easy?

Too difficult

If a normal distribution curve is negatively skewed this means its too difficult or too easy?

Too easy

What does nominal mean