Booklet 1 Investigation Designs Flashcards
(21 cards)
What is a pilot study
A small scale trial run of the investigation/ experiment first, taking place before the real experiment
Allows researcher to find any problems and make modifications
Can also be checked to see if tasks are too easy (ceiling effect, everyone scores too high) or too hard (floor effect, everyone scores too low)
What is an aim
Broad statement of what is going to be investigated in the study
What is a hypothesis
Prediction of the findings
Precise and testable statement of the relationship between two variables
MUST BE OPERATIONALISED before study is conducted
What is an alternative / experimental hypothesis
A prediction of what the researcher thinks will happen to the DV when the IV changes
Can be directional or non directional
What is a Null hypothesis
States that the IV will have no effect on the DV and any observed differences will be due to chance
Difference between directional and non directional hypothesis
Directional = states the direction of the predicted difference between two conditions / two groups of ppts
Related to on tailed tests
Non directional = predicts there will be a difference between two groups / two conditions without stating the direction
Relates to two tailed test
What are participant variables and are they internal or external
How can they be controlled?
INTERNAL
Variables which are to do with the participants
Age, gender, social class, ethnicity
Can be controlled by RANDOMLY ALLOCATING participants to groups that any differences cancel each other out with a large enough sample
What are situational variables
Are they external or internal
How can they be controlled
EXTERNAL
variables to do with the situation which might interfere with and affect the behaviour of participants in an experiment
Time of day, lighting, temperature
Controlled by using STANDARDISED PROCEDURES AND STANDARDISED INSTRUCTIONS to ensure all ppts have the same experience
What are confounding variables
Extraneous variables that have not been controlled
May affect (confound) the results of the study and become confounding variables.
What are demand characteristics and how are they controlled
Aspect of the research situation which leads to ppts to guess the sun and change their behaviour accordingly, hence not behaving naturally
CAN AFFECT THE DV (example of an extraneous variable)
Controlled by:
-deception (ppts not told the aim)
- single blind method (ppts not told which condition they are in)
What is an investigator effect and how are they controlled
Anything the researcher does which can affect how ppts behave and the subsequent data collected
Can EFFECT THE DV = extraneous variable
Controlled by:
- double blind method (neither researcher nor ppts know what the hypothesis is about or which condition they are in)
= makes them more OBJECTIVE and LESS LIKELY to introduce investigator effects
What is reliability and how can it be tested
Whether a measure is CONSISTENT and STABLE over time
Test- retest
= check for external reliability, ppts tested once, same ppts then tested again at a later date, two sets of scores correlated to determine the extent to which test scores of the same person are SIMILAR
What is validity and the difference between internal and external
How Can it the measured
Whether a test measures hay it intends to measure
Internal = whether or not we can say the IV has caused the effect seen on DV.
Too little control (low validity) = May be confounding variables
External = extent to which results can be generalised to other settings
Too much control = behaviour studied might not be like real life
FACE VALIDITY = doing an ‘eyeball’ test (simply looking over the test to see whether it looks like it measures what it’s supposed to measure)
What is a sampling bias and how is it avoided
Occur if the sample selected is not representative of the rest of the target population
Avoid - sample should be as large as possible
Random sampling
Strength and weaknesses
Randomly allocate ppts into separate groups, each ppt can be allocated a number
S = best technique for being representative - every person in the population has an equal chance of being selected for the sample
N = sample May be unrepresentative, especially if the sample is too small - ppts with similar demographics could all be selected
What is opportunity sampling and it’s strength and weakness
Obtaining people who are available at a certain location as s certain time to take part in the research
S = it’s easier and more convenient than many other types - less time and resources required
N = sample isn’t likely to be representative - ppts drawn from one specific area and may not represent target population
ALSO researcher decided whom they approach to take part in research
What is volunteer sampling and it’s strength and weakness
SELF SELECTED - volunteers respond to an advertisement placed in a strategic position
S= it’s easier and more convenient than random sampling - requires minimal input from researcher (less money and time)
N= not likely to be representative - volunteers may be a certain profile and helpful and keen people which may affect the findings and may not be able to be generalised
What’s is systematic sampling and it’s strength and weakness
Every nth member of the target population selected and placed in conditions
S= convenient if sample is small - likely to get a complete sampling frame
N= difficult if the population is large and may still be unrepresentative - difficult to obtain complete sampling from large population so likely sampling isn’t representative
What’s stratified sampling and it’s strength and weakness
Researcher identifies key STRATA of target pop.
Calculates correct proportions from each STRATA based on proportions of pop
Proportions of sample should REFLECT proportions of target pop
S= likely to be the most representative of all - method makes sure strata in sample reflect strata in target pop
N= requires most amount of time and resources
What is standard deviation
Measure of variability (spread) that takes into account alls cores and their difference from the mean value
LARGER THE DEVIATION = GREATER THE SORESD OF SCORES
What are the ethical guidelines
Rights to withdraw - ppts informed they can drop out of study at any time and HOW + can withdraw their data at later point up to a certain date before publication
Debriefing - speak to all ppts at end explaining fully what study was about and what results mean, asking for questions and making sure no harm was done - support must be provided
Protection from harm - researcher must not cause futures to pots - protected from physical and mental harm (special care received to vulnerable groups)
Deception - intentionally withholding info about study / aims from ppts (May be necessary to avoid DC) MAKING SURE TO DEBRIEF ASAP
Informed consent - ppts know as much as possible about prodedure before they agree (consent form)
Confidentiality - ppts privacy and identity is protected at all times (pseudo names)
Observational research - research only allowed to be completed in public domain BUT not (churches schools, toilets) without consent
