COGNITIVE - RESEARCH METHODS

Question 1

lab experiments

Answer 1

AO1:
-lab expts take place in a controlled environment with artificial conditions
-the IV is manipulated to see the effect of this change on the DV, which is measured
-the room may/may not have specialised equipment due to the nature of the expt
-often, there is an experimental group (who receive the conditions) and a control group (who provide a baseline measure). The results of these groups then get compared

AO3: EVALUATION
(strength)
->high reliability due to standardised procedure
–>all lab expts use a SP, meaning it is easy to replicate
–>therefore, we can test the results for consistency

(weakness)
->low ecological validity
–>the artificial setting/task may produce unnatural behaviour that does not reflect real life
–>therefore, low mundane realism means that we cannot generalise the findings to a real life setting

(strength)
->high internal validity
–>the high control over the environment means high control over EVs
–>therefore, allowing a cause & effect relationship to be established

(weakness)
->low internal validity: can’t control demand characteristics
–>ppts know they’re being studied & therefore may act unnaturally
–>this causes confounding variables during the study, causing inaccurate findings

Question 2

field experiments

Answer 2

-field expts take place in the ppts natural setting to provoke natural reactions
-the IV is manipulated to see the effect the change will have on the DV, which is measured
-it may use both an experimental group and a control group to use as a baseline to compare what the DV would be like without the manipulation of the IV
-ppts are likely to be randomly allocated to either group to remove bias, often through using an opportunity sample (whoever is available at the time)

A03: EVALUATION
(strength)
->high ecological validity
–>ppts are in their natural setting and their behaviour will reflect real life
–>therefore increasing the accuracy of the findings

(weakness)
->EVs/CVs are hard to control
–>eg. you can’t control the weather conditions, meaning there is no SP
–>therefore, decreasing the reliability as it can’t be exactly replicated

(strength)
->better control over demand characteristics than a lab expt
–>ppts are unaware they’re being studied, therefore they won’t change their behaviour
–>therefore, increasing internal validity

(weakness)
->low internal validity
–>the lack of control over EVs/CVs means we cannot say for certain if the IV is affecting the DV

Question 3

variables

Answer 3

IV = the variable that is manipulated by the experimenter in order to test it’s effects on the DV
DV: the variable that is measured/a measurable outcome of the action of the IV in an expt
EVs: factors that could impact the results of the study that are identified BEFORE the study is conducted
CVs: factors that could impact the results of the study DURING the study

PARTICIPANT VARIABLES:
->what are ppt variables?
–>(include) mental health, ability/skill, age, demand characteristics, IQ, mobility
->how do we control them?
–>counterbalancing, experimental method (eg. repeated measures), ensure the sample have the same IQ, mobility, skill, are the same age, etc, screen for mental health issues/learning difficulties and alter the sample accordingly

SITUATIONAL VARIABLES:
->what are situational variables?
–>withdrawal from expt, weather conditions, time of the day, disruptions from environment (eg. noise/lighting)
-how do we control them?
–>complete the study is a lab or controlled environment rather than a field expt, pilot study, use a standardised procedure so it can be exactly replicated

EXPERIMENTER BIAS:
->what is it?
–>mannerisms/body language shown by the experimenter which may intentionally/unintentionally influence ppt behaviour, causing inaccurate results
->how do we control it?
–>single blind procedure to remove demand characteristics (ppt doesn’t know which condition they’re in but experimenter does)
–>double blind procedure to remove experimenter bias (neither ppt nor experimenter know which condition the ppt is in)

Question 4

sampling techniques

Answer 4

RANDOM SAMPLING:
->a sample in which every member of the target population has an equal chance of being chosen (eg. random name generator)
-> (strength) best for producing an unbiased, unrepresentative sample of the target population, making the results highly generalisable
-> (weakness) can be very time consuming ad is often impossible to carry out, especially when you have a large target population

STRATIFIED SAMPLING:
->(best and most representative!!!)
->involves classifying the population into categories and choosing a sample that consists of ppts from each category
-> (strength) every part of the group will represent the target population
-> (weakness) can be very time consuming as the categories have to be identified and calculated

VOLUNTEER SAMPLING:
->(aka “self selective sampling”)
->ppts volunteer to take part in expts, usually from adverts posted online or locally
-> (strength) quick and easy, and can reach a wide variety of ppts
-> (weakness) results cannot be generalised as it is a biased sample of ppts, they must all be highly motivated to do the task as they volunteered

OPPORTUNITY SAMPLING:
->consists of taking a sample from people available at the time of the study and fit the required criteria
-> (strength) easy in regards to time and money
-> (weakness) can’t generalise as it may produce a biased sample as it is easy for researchers to choose people from within their own social group

Question 5

experimental design

Answer 5

INDEPENDENT MEASURES:
->ppts only take part in one condition of the IV, multiple groups are used for different conditions
->(strength) the control group’s behaviour acts as a baseline for the effect of the IV to be measured against, so cause & effect can be established
->(weakness) risks ppt extraneous variables, eg. ppts in group 1 may have a higher IQ than ppts in group 2

REPEATED MEASURES:
->one group takes part in both conditions of the IV
->(strength) removes the risk of ppt variables as they don’t need to be matched to another group with the same IQ/skill-set/age/etc
->(weakness) risk of order effects (eg. boredom & fatigue

MATCHED PAIRS:
->ppts are matched with a partner of a similar age/IQ/skill-set; one partner will be in the experimental group and one will be in the control group
->(strength) accurate control group to provide a baseline for the IV to be measured against/compared to
->(weakness) still not 100% accurate as ppts can never be exactly matched, meaning there is still a risk of ppt variables