Research methods Flashcards
What is the difference between a directional hypothesis and a non-directional hypothesis?
In a directional hypothesis the researcher clearly states the difference that is anticipated between two conditions while a non-directional hypothesis states that there is a difference but doesn’t specify.
What kinds of words are used in a directional hypothesis?
Less or more, higher or lesser, faster or slower
How would you operationalise a hypothesis?
Clearly define variables in terms of how they can be measured. eg. After drinking 300ml of coke, the group will be able to say more words in the 5 minute time period than the group who drinks 300ml of water.
What are independent variables and dependent variables?
IV: The variable that changes
DV: The variable that is measured
What are extraneous variables and confounding variables?
EV: Any variable other than the independent variable that may affect the dependent variable if not controlled
Confounding variable: A variable that can’t be predicted or controlled eg the weather
What is it called when a participant may be aware of the purpose of the study and therefore alter their behaviours and attitudes?
Demand characteristics
Give a reason why repeated measures may not work for certain experiments?
The ppts may develop demand characteristics, altering the results of the experiment
Give a positive of the repeated measures experimental design
It gives two sets of results using the same sample, meaning that it guarantees a comparison
What’s the difference between experimental types and experimental design?
experimental types: lab experiments, field, quasi etc
Experimental design: repeated measures, independent groups, matched pairs
Give a weakness of using matched pairs
There may still be important differences between partners, affecting the DV - decreased reliability
What type of experimental design is suitable for this experiment?
Depressed patients assigned to receive either cognitive therapy or behaviour therapy for a 12-week period. A standardised test for depression was administered and participants were paired on the severity of their symptoms.
Matched pairs
Describe internal and external validity
Internal validity is including what goes on within the experiment while external validity is about generalising the findings to other situations
Give 2 strengths of a lab experiment
High internal validity due to the control of variables + standardised instructions increase repeatability and therefore reliability
Give 2 weaknesses of a lab experiment
Can lack generalisability and has low ecological validity - artificial situations + demand characteristics are common, lowering reliability
Compare quasi and natural experiments
natural experiments are where a researcher takes advantage of a pre-existing independent variable (ppts may be tested in lab or field), while quasi experiments have an IV that is based on an existing difference between people eg age, gender
Give one strength and one weakness of a field experiment
Strength: high ecological validity - more real life applications therefore high reliability.
Weakness: ethical issues such as informed consent and confidentiality
Name as many types of bias as you can
Researcher bias, social desirability bias, culture bias, sampling bias
Give a strength of a random sample
No researcher bias - they don’t choose people that could support their hypothesis
What is volunteer bias and why is it a problem for the volunteer sample method?
The volunteer method may attract a particular profile of individual, eg. someone who is interested in what you are investigating and therefore knows more about it (demand characteristics)
Name a strength of systematic sampling
Avoids researcher bias
How would you obtain informed consent from people under 18yrs old?
A letter/email to the parents detailing the experiments aims and procedure - allowing them to sign and consent on behalf of the child
Describe presumptive consent and why would this be used?
A similar group of people are asked if the study is acceptable - used when the researcher doesn’t want to spoil experiment
Under what circumstances is deception allowed?
If it wouldn’t cause the ppt undue stress
What should happen at the end of a study?
Debrief - Gives individuals a right to withdraw
How are personal details protected?
Anonymity - not identifying name
Define the term ‘pilot study’
Small scale version of an investigation - aiming to check that procedures work
What is the key difference between a natural and controlled observation? And give an example of a controlled observation
Natural - Context where the behaviour would usually occur, aspects of the environment are free to vary.
Controlled - Control over EV’s eg. Mary Ainsworth’
s strange situation
Define covert and overt observations
Covert - Ppt’s behaviour is being watched without their knowledge
Overt - Ppt’s behaviour is being watched with their knowledge
Explain a weakness of covert observations
Ethical issues regarding informed consent as the participant may not want to be studied and issues with confidentiality
Define ppt and non-ppt observations
Ppt - researcher becomes a member of the group being observed
Non - ppt - researcher is outside of the group
Explain 2 strengths and 2 limitations of questionnaires
Strengths: Cost effective - Generates a large amount of data without the researcher being present and can be easily accessed
Data is usually quantitative - Closed ended questions makes it easy to analyse and put into a statistical graph HOWEVER, low reliability as closed-ended questions may be interpreted wrong, social desirability bias and may not match how the person feels.
Demand characteristics - People will be aware of what the researcher is looking to find out
Give a strength and weakness of structured interviews
Easy to replicate (standardised instructions)
Difficult to go further into detail
Give a strength and weakness of unstructured interviews
More flexibility - higher reliability as more detail is given
Analysis of data = qualitative - difficult to analyse
Give a weakness of a meta-analysis
Researcher bias and time consuming
Give a strength of a meta analysis
Increases sample size - high reliability
What does a large standard deviation mean?
Suggests that not all ppts were affected in the same way by the IV or few anomalous results
What is a positive skew on a distribution graph?
Most of the distribution is concentrated to the left
Outline the sign test in 5 steps
- Convert the data to nominal data by subtracting the score on any column from the other column. If the answer is negative, put a - and if its positive put a + (the ones that are the same dont matter)
- Add up the pluses and minuses
- Take the less frequent sign and call this S
- Compare calculated value (S) to critical value 0.05/5%
- if the value is lower than the critical value it is significant
What is the critical value?
0.05
What are 3 aims of peer reviewing?
Allocate research funding
Validate quality and relevance of research
Suggest improvements
