Research Methods Flashcards
(105 cards)
what is the IV
The independent variable is the one that is manipulated/changed by the researcher and is the difference between the two conditions
What is the DV?
The dependent variable is the one measured by the researcher
What is an operationalised variable?
IV’s and DV’s must be fully operationalised this means stated in a measurable form. This ensures the experiment can be repeated in exactly the same way with the variables being manipulated and measured in the same way.
How do you operationalise the IV (using oj experiment as an example)
The temperature of the room, there will be a hot room condition and a cold room condition
How do you operationalise the DV (using oj experiment as an example)
The volume of orange juice consumed in one room (measured in cm^3)
What are hypotheses?
A hypothesis can be defined as a precisely worded testable statement, made at the outset of an investigation, which indicates the expected outcome of a study
The alternative (experimental) hypothesis: States that the expected effect of the manipulated variable on the outcome is statistically significant
May be a directional or a non-directional hypothesis
what does a null hypothesis do?
States that there is no effect in a study
What does an experimental hypothesis do?
An experimental hypothesis predicts the effect the IV will have on the DV - that is, what we expect will come out of the manipulation of the independent variable.
what is a directional hypothesis?
In a directional hypothesis a researcher makes clear the sort of difference that is anticipated between two conditions or two groups of people. For this reason directional hypothesis’s include words like more or less, higher or lower, faster or slower
how do you write a null hypothesis?
- there will be no difference…
- …any difference will be due to chance
What are extraneous variables?
These are other factors apart from the independent variable that can affect the outcome of an experiment. The only thing that should influence the DV is the IV. Any other variables that might potentially interfere with the IV or DV should be controlled or removed these are known as extraneous variables
what are confounding variables
Any variable other than the IV may have affected the DV so we cannot be sure of the true source of changes to the DV. Confounding variables are a type of extraneous variable but what makes them confounding is that they are impossible/ very difficult to control for
What is an independent groups design?
Different participants are used in each condition of the independent variable.
This means that each condition of the experiment includes a different group of participants
This should be done by random allocation, which ensures that each participant has an equal change of being assigned to one group or the other
evaluation of independent groups design
- reduces order effects as they are only doing one condition of the independent variable
- demand characteristics aren’t likely as participants only participant in one independent variable condition
- there may be participant extraneous variables
- poor control as there are different participants are in each condition
what is a repeated measures design?
The same participant takes part in each condition of the independent variable. This means that each condition of the experiment includes the same group of participants.
evaluation of repeated measures design
- Individual differences between participants are eliminated
- There may be order effects (practice, boredom, fatigue), which may reduce internal validity as the participant behaviour in the second condition may be affected by having already participated in one condition
- Demand characteristics are more likely as participants experience both conditions
What is a matched pairs design?
Participants are paired together on a variable or variables relevant to the experiment. For example- each member of one group is the same age, sex or social background as a member of the other group. A matched pairs design is similar to independent measures as in each, each participant only takes part in one condition.
evaluation of matched pairs design
- reduces participant extrenuous variables, as the people are similar, so similar results should be yielded, therefore there is good control
- order effects are limited, as the participants only participate in one condition
- unlikely to be any demand characteristics as they only participate in one condition
- very hard to find two people who are 100% the same
what are the ways to limit order effects?
Counter balancing- systematic variation of the order of conditions in a study to minimise the influence of extrenuous order effects on experimental results
Randomisation- the order of the presentation of the trials is shuffled to prevent order effects
what is event sampling?
event sampling- a target behaviour or event is first established, then the researcher records this event every time it occurs
what is point sampling?
point sampling- point sampling means that a researcher makes note of the behaviour of each participant and then moves on to the next participant. If the researcher is studying time “on-task” in the classroom , he may note what student 1 is doing, then student 2, then student 3, and so on
what is time sampling?
time sampling- a target individual or group is first established then the researcher records their behaviour in a fixed time frame, e.g. every 60 seconds
what is inter observer reliability?
inter-observer reliability- it is recommended researchers do not conduct observations alone as this introduced bias to the research. To make data recording more objective and unbiased observations should be carried out by at least two researchers. If the observers get the same or similar data, the results are said to have high inter observer reliability
what are behavioural categories?
behavioural categories- when a target behaviour is broken up into components that are observable and measurable