Research Methods Flashcards
- Aim =
- Hypothesis =
- general statement about purpose of the study
- clear testable statement that states realtonship between variables as stated at the start of the study. It is the prediction.
Three steps to make a strong hypothesis
T - testable > a way of testing the hypothesis
O - operationalised> making sure the variables are measurable, eg; specific measurement like cm or metres or test score
P - precise
EG: participants who drink one can (O) of red bull a dat will stay awake for more hours ( DIRECTIONAL) than people who dont.
Three types of hypothesise
Directional - clear difference anticipated between two conditions/ groups
eg: girls are faster than boys at running
Non- Directional - only states that there is a difference between conditions/ groups.
eg: girls and boys have different levels of running ability.
Null hypothesis - when there is no difference between any condiiton
When to use what hypothesis
Directional: when there are previous studies/theories that suggest a particular outcome\
If there is no previous studies or evidence then jsut non directional
What is an IV
A DV
IV - variable manipulated by researcher
DV - is measured by the researcher
How to test effect of an IV
Two levels
Control condition- no chocolate ( as a comparison )
Experiment condition - yes chocolate
Situational variables
environmental variables, weather, time of day..
Participant variables
participant influences, their intelligence,personality, age
Investigator variables
unwanted influence from the investigator in the reasearchs outcome.
bias, instructions, facial expression, leading questions, smiling, uniform.
Target population
target population - individuals a researcher is interested in experimenting on
Sample population
impossible to practically study everyone in target population so you use a sample of the target population. Sample must be representative so findings can be generalised.
Random sampling
-every member of population have an equal chance of being selected
-Computer generated randomiser
- Numbers from a hat
Opportunity sampling
people who are available to the researcher
Use anyone willing to take part
Student opportunity sampling
Volunteer sampling
self selected
Participants volunteer to participate
Usually through newspaper ads
( Milgram/Zimbardo )
Stratified sampling
Match up sample to target population
How to:
- identify different sub groups that make up population
- worldwide out proportions needed for sample needed to be representative
- participants from sub groups selected through random sampling
Systematic sampling
Every nth number of the target population is selected ( every 6th person in a list of population )
Pros/ cons: volunteer sampling
Pro
- cheap and quick and minimal effort
Cons
- demand characteristics: ( screw u / please you effect )
- low population validity and biased.
Pros/ cons: opportunity sampling
Pros
- cheap and easy
Cons
- low population validity ( usually uni students who volunteer) not representable
- researcher bias, lot of control over who is used in the study
Pros/ cons: random sampling
Pros
- representative and has good population validity
- low researcher bias
Cons
-time consuming
- not always random, can still end up with biased sample
Pros/ cons: stratified sampling
Pros
- representative, shows unbiased sample of population
- more generalisable
Cons
- time consuming
- cant always get a big enough sample