Scientific processes Flashcards
Define aim
An aim is a precise statement of why a study is taking place
What should an aim include
What is being studied
What the study is trying to achieve
Where do aims come from?
Personal interests of the researcher
Other researchers theories / studies
Seek a solution to a practical problem
Define hypothesis
A statement of prediction that is directly testable
Define directional / one-tailed hypothesis
Predicts the direction in which change is expected to occur
Words eg faster/slower, bigger/smaller, more/less
Define non-directional / two-tailed hypothesis
Simply predicts the change and does not specify the direction
Words eg change, effect, difference
Define null hypothesis
Predicts there will be no change and that any change is due to chance
What must be identified in the hypothesis
Independent variables
Dependent variable
^operationalised
Define independent variable
The thing that changes
Define dependent variable
The thing that is measured
Define operationalised
Stated in a measurable form
Define extraneous variable
EVs do not vary systematically with the IV
Any variable other than the IV which may HAVE AN EFFECT on the DV
Therefore may affect validity of research findings
Can extraneous variables be controlled?
Yes
Define confounding variable
CVs vary systematically with the IV
Any variables other than the IV which may HAVE EFFECTED the DV
So we cannot know the true cause of the changes to the DV
Can confounding variables be controlled?
No
Name the two types of extraneous variables
Participant variables
Situational variables
Define participant variables
Individual differences between RPs that can affect the results
Give examples of participant variables
Age Gender Intelligence Social class Fitness
How can the researcher reduce the effects of participant variables
Careful selection of RPs as researcher can do little to control them
Controlled across different experimental conditions
Define demand characteristics
Cues which convey to the RP the aim of the experiment
Give examples of demand characteristics
Instructions given to RP What RP has heard from others The way RP was approached initially Setting of experiment Whether the experimenter is formal or relaxed
What might demand characteristics lead to?
Participant reactivity
Define participant reactivity
The way RPs change their behaviour due to cues given as demand characteristics
Give examples of participant reactivity
Please you effect - try to help researcher
Screw you effect - try to ruin results
How can demand characteristics / participant reactivity be controlled?
Single blind trial - RP does not know which condition they are in, this prevents them seeking clues about the aim
Define situational variables
Outside influences on the experiment
How can situational variables be controlled?
Standardisation
Randomisation
Counterbalancing
Define standardisation
Ensuring all RPs are tested under the same conditions
Identical.. instructions, procedures followed, scoring techniques, environment
Define randomisation
Order of tasks / presentation of data etc is decided on the toss of a coin / another random method of selection to control for order effects
Define order effects
Order effects occur when an RP undertakes a task more than once
Give examples of order effects
Practise
Fatigue
Boredom
Define counterbalancing
Used to control order effects when using the repeated measures design.
Changes order of tasks for each RP / ABBA technique
Define investigator effect
If the researcher changes in any way while in different conditions it could affect the results
Give examples of investigator effects
Change in... Mood Appearance Instructions they give Leading questions
How to control investigator effects / order effects
Double blind trial - neither RP or researcher knows which condition they are in -> can’t communicate cues about aims
Name the types of experimental design
Independent measures design
Repeated measures design
Matched pairs design
Define independent measures design
Uses different participants in each condition.
Each RP only takes part in one condition
What are the strengths of using independent measures design?
No order effects
Demand characteristics are less likely to affect results, as RPs only take part in one condition so are less likely to guess the aim
What are the limitations of using independent measures design?
Individual differences occur due to participant variables -> random allocation reduces this
More RPs will be needed -> less economical than repeated measures design
Define repeated measures design
Uses the same participants in each condition.
Each RP takes part in both conditions
What are the strengths of using repeated measures design?
No participant variables -> no individual differences
Fewer RPs needed than independent measures design -> important when RPs are in short supply
What are the limitations of repeated measures design?
Results can be affected by order effects -> reduces validity of findings -> counterbalancing can reduce this
Demand characteristics may affect validity of results
Define matched pairs design
Uses different but similar participants in each condition e.g. Twins
Matching based on important characteristics that might affect performance e.g. Driving ability, alcohol tolerance
What are the strengths of using matched pairs design ?
No order effects
Individual differences are reduced
Demand characteristics are reduced
What are the limitations of using matched pairs design?
Need lots of RPs, some are wasted if they can’t be matched up
Difficult to march RPs exactly -> even with identical twins there are important differences which could affect DV
Give examples of situational variables
Time of day Weather Noise Type of room Design of experiment as RPs may only experience one condition
Define sampling
The process of selecting RPs to study from the target population
Define target population
A specified section of humankind
Why must the sample group be representative of the target population ?
So that the results can be generalised to the whole target population
How large should a sample group be?
Big enough for it to represent the variety of individuals in the target population
Not so big as to make the study uneconomical in terms of time and resources
What is random sampling?
All members of the target population have an equal chance of being selected.
Does not guarantee a representative sample , but chances of bias are unlikely
E.g. Pull names out of a hat
Give the strengths of using a random sampling technique
Best chance of getting an unbiased sample as researcher has no influence over who is chosen
Give the limitations of using a random sampling technique
Representation is not guaranteed.
Still possible that a bias sample may be produced -> limits generalisability
What is systematic sampling?
RPs are selected from a list at fixed intervals
E.g. Every fifth person
Interval number can be determined randomly -> reduce bias
Give the strengths of using a systematic sampling technique
If list order is randomised, offers unbiased chance of gaining representative sample
It’s an objective method
Give the limitations of using a systematic sampling technique
Time and effort required
Requires complete list of population
What is stratified sampling?
Target population is divided into sub-sets e.g. Age, gender, class…
Random sample is taken from these sub sets (strata)
This ensures representative sample is taken
Give the strengths of using a stratified sampling technique
May be more representative -> effort is made to identify important characteristics of target population
More generalisable than other methods
Give the limitations of using a stratified sampling technique
Time consuming to sort categories + calculate
If stratification isn’t perfect, a complete representation isn’t always possible
What is opportunity sampling ?
Aka convenience sampling
Involves selecting anyone who is available from the target population .
Effort may be made to reduce bias by e.g. picking equal numbers of males / females
Give the strengths of using an opportunity sampling technique
Quick + convenient -> most economical
Most commonly used method
Give the limitations of using an opportunity sampling method
Unrepresentative of target population -> will be selected from very specific area eg a street
Can be biased on the part of researcher who may choose a RPs most likely to be helpful
What is volunteer sampling?
Participants volunteer in response to an advertisement e.g. Newspaper / notice board
Give the strengths of using a volunteer sampling method
Convenient
Ethical
Choice isn’t biased on the part of researcher
Give the limitations of using a volunteer sampling technique
Biased
Unrepresentative
RPs may share certain traits e.g. Keen, curious, confident -> participant variables
Difficult to generalise results
Define ethics
Standards of conduct that distinguish between right and wrong, good and bad, justices and injustice
Who created the ethical guidelines that all practicing psychologists must follow and why did they create them?
British Psychological Society (BPS)
To protect participants and the reputation of psychology
What is an ethical issue?
Any situation that repeatedly gives rise to an ethical dilemma
Name all the issues raised in the BPS ethical guidelines
Informed consent Deception Protection from harm Confidentiality Withdrawal Diebriefing
What is informed consent?
When a RP agrees to take part in a study, based on information made available to them about the research
When might not gaining informed consent ethically acceptable?
So long as what happens to the participants could just as likely happen to them in everyday life
E.g. Observation in natural setting
What is the age restriction for giving consent to take part in a study?
16
If the RP is under 16, consent should be given by their parents
What is an issue with getting informed consent?
The researcher may ‘give the game away’ -> influence RP behaviour
Therefore withholding information is sometimes justifiable
What is deception?
Information is withheld from RPs
They are misled about the purpose of the study and what will happen during it
What does the BPS guidelines say about deception?
“Intentional deception should be avoided whenever possible”
It is particularly unacceptable if it leads to “discomfort, anger or objections from the participants when the deception is revealed afterwards”
What must the researcher have done in order for deception to be accepted as unavoidable?
Make sure all alternative procedures which avoid deception are unavailable
Consult with colleagues about how RPs might be affected by the deception
Reveal the deception immediately after the research is complete
What is protection from harm?
“Investigators have a primary responsibility to protect participants from physical and mental harm during the investigation”
Risks must be no greater than risks in everyday life
Investigator has responsibility to detect and remove any consequences of the research
What is confidentiality?
RPs must be told that there is no need to answer any personal questions and if they do, their answers will be treated in confidence (anonymous)
What is right to withdraw?
Participants have a right to withdraw from an investigation at any time, during or after the research has taken place.
Including if they’re being paid .
No attempt should be made to dissuade them
What is debriefing?
Disclosing after the experiment... Aims of study How RP has contributed Any deception is explained + justified Attempts to undo any negative affects
How is the issue of deception dealt with?
Debriefing
Retrospective informed consent
How is the issue of not getting informed consent dealt with?
Presumptive consent
Prior general consent
Children get consent from parents / those in loco parents e.g. Head teacher
Define Retrospective consent
The true nature of the study is revealed after it has taken place.
The participants then decide whether they want to withdraw their results
Define presumptive consent
A large random sample of the population is told all about the study (inc deception) and asked whether they would agree to it
If they agree, we assume that everyone would agree
Define prior general consent
Before the study , RPs are asked whether they would object to any deception should it be necessary
How is not protecting participants from harm dealt with?
Right to withdraw
Confidentiality
Debriefing
Researcher is responsible for stopping the study
How is the issue of confidentiality dealt with?
Keeping everything in private
Number RPs / use their initials
Only researcher has access to data
Names are usually irrelevant, even researcher doesn’t need to know it
What are the possible consequences of breaking the issue of deception?
Prevents informed consent
Makes participants distrustful of the researcher and any future research they may take part in
What are the possible consequences of breaking the issue of informed consent?
Makes participants distrustful in the future
What are the consequences of breaking the issue of protecting participants from harm?
May impact on their future lives
Stop them wanting to take part in future research
What are the possible consequences of breaking the issue of confidentiality?
Participants won’t trust researchers in the future
Feelings may be hurt
Could affect RPs lives psychologically
What are the reasons ‘for’ and ‘against’ breaking ethical guidelines?
For - value of research may be ground breaking
Against - damaging effect on participants / reputation of psychology
What is a pilot study?
A small scale study carried out before the main research
Why do researchers do pilot studies?
Allow researcher to identify any potential issues (EVs), and to modify the design / procedure -> save time and money
Test materials used
Test RPs understand standardised instructions
Test timings are suitable
Test if questions are leading
Test if behaviour categories are appropriate
