Cognitive Research Methods Flashcards
What are experiments the only research method to do?
The only research method that detrmine cause and effect.
What is a lab experiment?
An experiment conducted in a controlled, artificial environment.
IV is manipulated
DV is measured
eg Baddeley
What is a field experiment?
An experiment that takes place in a natural setting.
IV is manipulated
DV is measured
eg Sherif et al - Robber’s Cave
Strengths of Lab experiments
Reliable - removes the potential for extraneous variables
Validity - Gives a level of control over variables to achieve a more scientific approach
Weaknesses of Lab experiments
Ecological Validity
Validity - Demand Characteristics
Validity - Experimenter Effects
Strengths of Field Experiments
Ecological validity
Validity - No demand characteristics
Weaknesses of Field Experiments
Reliability - extraneous variables
Ethics - No consent, right to withdraw
What is an independent variable?
A variable that is manipulated or changed by the researcher in order to demonstrate a difference between the experimental conditions.
What is a dependent variable?
A variable that is measured or the result of the experiment. Measure any changes that occur due to the IV.
Allows causality to be established (cause and effect)
What is operationalisation?
Stating exactly what the independent variable is and exactly what is measured by the dependent variable.
What does operationalisation increase within the experiment?
Objectivity
Reliability
What is a hypothesis?
A prediction of what will happen in the investigation based on previous knowledge, research or theory.
What is an experimental/alternative hypothesis?
What are the 2 types?
A prediction for which we know the likely outcome.
Directional
Non-Directional
What is a Directional (one-tailed) hypothesis?
A hypothesis when we are certain of a specific outcome.
Strong evidence to suggest the outcome may happen.
(eg Males will gain higher grades in the maths exam than females)
What is a Non-Directional (two-tailed) hypothesis?
A hypothesis when we are not certain of the specific outcome.
There are conflicting theories or a lack of relevant evidence.
(eg There will be a difference in maths exam grades between females and males)
What is a Null Hypothesis?
A default prediction (a researcher can fall back on)
When the difference or relationship is too small or insignificant to be due to anything other than chance variables.
(eg There will be no difference in the length of time spent purring by cats that are fed tinned food or dry food)
What is the aim of an experiment?
A general statement about what area or topic is being researched.
What is independent group design?
When the ppts are divided into groups and are only involved in one of the experimental conditions.
Strengths of independent group design
Less likely to guess the aim of the investigation - lower chance of demand characteristics or expectancy effects
Weaknesses of independent group design
Need to recruite more people
Individual differences or participant variables - make comparisons hard and may affect the validity
To control for individual differences - randomly allocating ppts
What is repeated measures design?
When all ppts take part in all conditions of the experiment.
Strengths of repeated measures design
Removes issues of individual differences
fewer ppts are needed - more economical
Weaknesses of repeated measures design
Higher chance of demand characteristics
What is matched pair design?
When different ppts are assigned to each condition but they are matched on characteristics that are important to the study.
Usually done through pre-testing and researching the lives/backgrounds of all the ppts
Strengths of matched pair design
More reliable - comparison
differences are more likely to be due to IV so causation can be established
Weaknesses of matched pair design
Very difficult to match ppts on all possible characteristics
Time Consuming
Have to cut some ppts out as they don’t match
What is the Order Effect?
When the performance of ppts in one condition is influenced by the previous conditions of the experiment.
Includes practise (may become better as have learnt it in the condition before) and fatigue effects (become tired and perform worse)
How can order effects be controlled for?
Counterbalancing
Randomisation
Leaving a time gap between completing conditions
What is counterbalancing?
Involves the ppts being placed in 2 groups but all ppts still do all conditions.
Group 1 does condition A and then B
Group 2 does condition B and then A
A more complex way can be used (ABBA) and the mean for the conditions are used.
What is randomisation?
Involves selecting at random which of the conditions of the experiment a ppts does first. Can be done by picking names out a hat.
What are extraneous variables?
Factors (such as situational and ppts variables) that may have an unwanted effect on the dependant variable.
What is a confounding variable?
When an extraneous variable is not controlled for and therefore does have an influence on the DV, making it look as if the effect was from the IV.
What is a situational variable?
Types of extraneous variables that is found in the environment in which the study is conducted.
eg light, noise, temperature, other people, disturbances, time of day etc
What is a participant variable?
Types of extraneous variables where the ppts may affect the results of the study.
eg intelligence, motivation, personality, experience, age, skills etc
What is being obejctive?
The need to be impartial and judgement free.
Cognitive psychologists would agree that we can’t objectively measure mental processes, but we can objectively observe the data produced by experiments.
What is internal validity?
How well the procedure of a study establishes a causal relationship between the IV and DV.
What is construct validity?
A type of internal validity.
How well the measure of a behaviour is being used is a useful indicator of what is supposed to be studied.
eg recall of a previously learned list is not good to study episodic memory as they may draw on semantic memory
What is predictive validity?
A type of internal validity.
The extent to which the performance on the measure can predict future performance on a similar criterion.
eg if an intelligence test can accurately predict future academic success, then it has predictive validity
What is external validity?
How well research finding can be genaralised beyond the study itself to other situations or populations.
What is ecological validity?
A type of external validity.
The extent to which the place the research was natural.
What is task validity?
A type of external validity.
How realistic the task carried out in the experiment is.
What is population validity?
A type of external validity.
The extent to which research findings apply to other populations than those used in the smaple.
What is the experimenter effect?
The way an experimenter may influence the outcome of an experiment.
such as The Hawthorne Effect
What are demand characteristics?
When the ppts guess the aim of the experiment and change their behaviour to meet the expectations of the experimenter or to give the opposite results that they think the experimenter wants.
What is a single-blind procedure?
Where the ppts are unaware of the study aim.
Controls for demand characteristics.
What is a double-blind procedure?
Where neither the ppts or researcher who carries out the experiment knows the aim of the study.
Controls for experimenter effects.
