Research methods Flashcards
What is the difference between an aim and a hypothesis?
- An aim is a general statement made by the researcher which tells us what they plan on investigating
- A hypothesis is a precise statement which clearly states the relationship between the variables being investigated
What is the experimental method?
While all other variables are held constant, one variable is manipulated (IV) and the effect of this on another variable is measured (DV)
What is the difference between a directional and non-directional hypothesis?
- A directional hypothesis states which way you think the results are going to go
E.g. Eating smarties will significantly improve an individual’s dancing abilities - A non-directional hypothesis simply states that there will be a difference between the two groups/conditions but does not say which will be greater/smaller, quicker/slower etc
E.g. There will be a difference in male and female performance in a driving test
Used when there is little or no research or the findings are ambiguous
What is a natural experiment?
A natural experiment is an experiment in which the IV is not brought about by the researcher hence would have happened even if the researcher had not been there e.g. if studying reactions to earthquakes
What are the limitations of a natural experiment? (A03)
- Natural occurring events: may be rare so these experiments are not likely to be replicable - hard to generalise findings
- Very difficult to randomise participants into groups: confounding and extraneous variables become a problem
What are true experiments?
True experiments control the variables under investigation, and randomly allocate participants to groups
Lab and field experiments are both true experiments
What is an extraneous variable?
An extraneous variable is any variable that you’re not investigating that can potentially affect the outcomes of your research study
Doesn’t vary systematically with the IV - nuisance variables
What is a confounding variable?
A confounding variable is a variable other than the independent variable that systematically affects the dependent variable
Difficult for the researcher to be sure of the origin of the impact of the DV as the confounding variable could have been the cause
What is the difference between randomisation and standardisation?
- Randomisation is the use of chance to reduce the effect of bias from investigator effects
- Standardisation describes using the exact same formalised procedures and instructions for every single participant involved in the research process - eliminates non-standardised instructions as possibly extraneous variables
What is operationalisation?
Making sure your variables are in a form that can be easily tested
What are the strengths of a natural experiment? (A03)
+ Provides opportunities: for research that would have otherwise been impossible due to practical/ethical reasons
+ High external validity: dealing with real-life issues
What are the 4 types of experiments?
Laboratory, field, natural, quasi
What is a lab experiment?
A lab experiment is an experiment that takes place in a special environment whereby different variables can be carefully controlled
What are demand characteristics?
Demand characteristics refer to any cue the researcher or research situation may give which makes the participant feel like they can guess the aims of the investigation. This can cause the participant to act differently within the research situation from how they would usually act.
What are the 3 types of experimental design?
Independent groups
Repeated measures
Matched pairs
What is a field experiment?
A field experiment is an experiment conducted in a more natural environment, not in a lab but with variables still being well controlled
What are the strengths and weaknesses of a field experiment?
Strengths:
- Naturalistic: so more natural behaviours hence high ecological validity
- Controlled IV
Limitations:
- Ethical considerations: invasion of privacy and likely to be no informed consent
- Loss of control: due to extraneous variables hence precise replication not possible
What is independent groups design?
Two different groups experience two different conditions - the IV is naturally occurring
What is a strength and weakness of quasi experiments? (A03)
+ Controlled conditions: hence replicable, likely to have high internal validity
- Cannot randomly allocate participants: may be confounding variables presented - makes it harder to conclude that the IV caused the DV
What are the weakness of lab experiments? (A03)
- Experimenter’s bias: can affect results and participants may be influenced by these expectations
- Low ecological validity: high degree of control makes situation artificial, unlike real life
What is the difference between external validity and internal validity?
- External validity refers to the extent to which the results of a study can be generalized to other settings (ecological validity), other people (population validity), and over time
- Internal validity is a measure of whether results obtained are solely affected by changes in the variable being manipulated (i.e. by the IV) in a cause-and-effect relationship
What is a quasi experiment?
A quasi experiment is an experiment whereby the IV has not been determined by the researcher, instead it naturally exists, e.g. gender difference studies
What are the strengths of a lab experiment? (A03)
+ High degree of control: all variables are controlled, IV has been precisely replicated - greater accuracy
+ Replication: researchers can repeat experiments and check results
What are the strengths of independent groups design?
+ Order effects can’t be observed as no participants are used in more than one condition
+ Data collection is less time-consuming - all conditions of the experiment can be conducted simultaneously
What are the weaknesses of independent groups design?
- Different participants need to be recruited for each condition - expensive
- Risk of participant variables affecting results between conditions, not just manipulation of the IV
What is an example of an independent groups experiment?
A study on sleep that explores how different amounts of sleep affect people’s reaction times. Whilst one group had 10 hours of sleep per night, the other group had 3
- IV: the amount of sleep (the manipulated variable).
- DV: (the measured variable) was their recorded reaction time
What is repeated measures design?
All participants take part in all conditions - same participants allocated to all groups
What are the strengths of repeated measures design?
+ Results won’t be subject to participant variables
+ Same participants used twice so extra participants do not need to be recruited
What are the weaknesses of repeated measures design?
- Risk of observing order effects, but this risk be reduced by counterbalancing (controlling order of variables so each order combination occurs the same number of times)
- If a participant drops out, data will be lost from all conditions of the experiment, not just one
What is an example of a repeated measures experiment?
- A study investigates whether Quizlet helps A-level psychology students better than traditional textbooks, assessing learning with tests
- If the researchers conduct a repeated measures experiment, all participants will use Quizlet and standard textbooks
What is matched pairs design?
A pair of participants are matched bases on key variables (age ,gender etc). One member is put in the control group and the other in the experimental group
What are the strengths of matched pairs design?
+ Order effects will not be observed as participants only take part in one condition
+ Reduced risk of participant variables affecting results between conditions - tailored participant-matching process
What are the weaknesses of matched pairs design?
- Different participants needed for each condition- difficult and expensive
- Matching is a complex process - difficult to match participants identically, so identical twins are often used
What is an example of a matched pairs experiment?
A study of 100 people for a new diet - each subject would be paired with another subject similar to them and then randomly allocated to either the control or experimental group
What are the 3 order effects?
- Demand characteristics- subtle hints that suggest to the participant what the experimenter predicts or hopes to find in the study
- Boredom
- Fatigue
What is random sampling?
This method gives every member of the target group an equal chance of being selected for the sample by assigning a number to each member, and then selecting from the pool using a random number generator
What are the strengths of random sampling?
+ Representative - each member has the same probability of being selected
+ No researcher bias - researcher has no influence over who is picked
What are the weaknesses of random sampling?
- Time consuming - need to have a list of the population (sampling frame) and then contacting them takes time
- Volunteer bias - participants can refuse to take part so can end up with an unrepresentative sample
What is opportunity sampling?
Participants happen to be available at the time which the study is being carried out so are recruited conveniently
What are the strengths and weaknesses of opportunity sampling?
+ Easy method of recruiting which is time saving and less costly
+ Covnenient
- Not representative of the whole population -findings can’t be generalised
- Researcher bias is presented as they control who they want to select
What is systematic sampling?
A predetermined system is used whereby every nth member is selected from the sampling frame consistently
What is a strength and weakness of systematic sampling?
+ Avoids researcher bias and usually fairly representative of the population
- Not truly unbiased unless you use a random number generator then start the systematic sample
What is stratified sampling?
- Stratified sampling involves selecting participants in such a way as to recreate the same proportions of those sub-groups (strata) that exist in the population
- Then select the sample from each strata using random number generators
What are the strengths of stratified sampling?
+ No researcher bias - the selection within each strata is done randomly
+ Produces representative data due to the proportional strata so generalisation is possible
What are the weaknesses of stratified sampling?
- Time consuming to identify strata and contact people from each
- Not completely representative - the identified strata can’t reflect all differences between the people of the wider population
What is volunteer sampling?
Involves self-selection whereby the participant offers to take part either in response to an advert or when asked to
What are the strengths and weaknesses of volunteer sampling?
Strengths:
- Easy and not time-consuming - quick access to willing participants
- As participants are willing to take part, they are more likely to cooperate in the study
Weaknesses:
- Volunteer bias - may attract a particular profile of a person (keen, curious) - generalisation is affected
What are pilot studies?
- Small, trial versions of proposed studies to test their effectiveness and make improvements
- They allow for modification of methodology where necessary