research methods (Paper 2) Flashcards
(264 cards)
Experimental method
Experimental method definition -
p. 166
A research technique that involves deliberately manipulating the IV to observe and measure any resulting changes in the DV.
This method is used to establish cause-and-effect relationships.
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Experiments can take place in controlled environments (laboratory experiments), real-world settings (field experiments), or involve naturally occurring variables (natural or quasi-experiments), depending on the level of control and realism desired.
Experimental method
Aim definition -
p. 166
A clear, general statement describing what the researcher intends to investigate. It outlines the overall purpose or focus of the study.
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Experimental method
Hypothesis definition -
p. 166
A precise, testable statement predicting the expected relationship between variables in a study. It is formulated before the research begins.
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Experimental method
Directional hypothesis definition -
p. 166
Predicts that a difference/relationship exists between variables, and also the specific direction of that effect (e.g., one group will score higher than another).
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Experimental method
Non-directional hypothesis definition -
p. 166
Predicts that a difference/relationship exists between variables but does not specify the direction of the effect.
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Experimental method
Variables definition -
p. 166
Any ‘thing’ that can vary or change within an investigation. In experiments, they are used to assess whether changes in one variable cause changes in another.
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Experimental method
Independent variable (IV) definition -
p. 166
The variable that is manipulated by the researcher, or changes naturally —to examine its effect on the dependent variable (DV).
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Experimental method
Dependent variable (DV) definition -
p. 166
The variable that is measured by the researcher. Any effect on the DV should have been caused by the change in the IV.
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Experimental method
Operationalisation definition -
p. 166
The process of clearly defining variables to specify how they can be measured and tested within the context of an experiment or study.
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Experimental method
Aim example: What might be the aim for a study who’s theory is that drinking energy drinks (in this case SpeedUpp) makes people more talkative? (Due to its caffeine and sugar)
p. 166
To investigate whether drinking energy drinks makes people more talkative.
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Experimental method
Directional Hypotheses example: What might be the directional hypotheses for a study who’s theory is that drinking energy drinks makes people more talkative?
p. 166
Directional hypotheses include words like more or less, higher or lower, faster or slower, etc. since they predicts that a difference/relationship exists between variables. Within a certain direction, so examples could be:
- People who drink SpeedUpp become more talkative than people who don’t.
- People who drink water are less talkative than people who drink SpeedUpp.
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Experimental method
Non-directional Hypotheses example: What might be the non-directional hypotheses for a study who’s theory is that drinking energy drinks makes people more talkative?
p. 166
A non-directional hypothesis simply states that there is a difference/relationship between variable. But the direction is not specified. Example:
- People who drink SpeedUpp differ in terms of talkativeness compared with people who don’t drink SpeedUpp.
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Experimental method
Experiment example: How might you conduct an experiment for e.g the energy drink theory?
p. 166
Which states that drinking energy drinks makes people more talkative.
Firstly, we are going to gather together two groups of people, let’s say 10 in each group (mostly because we only know twenty people).
Then, starting with the first group, we will give each participant a can of SpeedUpp to drink.
The participants in the other group will just have a glass of water each.
We will then record how many words each participant says in a five-minute period immediately after they have had their drink.
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Experimental method
How might you decide which type of hypothesis to use?
For e.g the energy drink theory.
p. 166
Psychologists tend to use a directional hypothesis when the findings of previous research studies suggest a particular outcome.
When there is no previous research, or findings from earlier studies, they will instead decide to use a non-directional hypothesis.
Even though SpeedUpp is a ‘new energy drink’, the effects of caffeine and sugar on talkativeness are well-documented. Therefore we will opt for a directional hypothesis on this occasion.
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Experimental method
IV and DV functions in an experiment:
p. 167
In an experiment, a researcher changes or manipulates the independent variable (IV) and records or measures the effect of this change on the dependent variable (DV). All other variables that might potentially affect the DV should remain constant in a properly run experiment. This is so the researcher can be confident that the cause of the effect on the DV was the IV, and the IV alone.
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Experimental method
Levels of the IV:
p. 167
To test the effect of an independent variable (IV), researchers create different experimental conditions—known as levels of the IV. These usually include a control condition (e.g., drinking water) and an experimental condition (e.g., drinking an energy drink). This allows for comparison and helps identify any effect of the IV on the dependent variable (DV). A good hypothesis should clearly show the IV, DV, and how they are operationalised (i.e., made measurable).
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Experimental method
Operationalisation of Variables:
p. 167
Psychological concepts like intelligence or social behaviour can be vague, so researchers must clearly define them in measurable terms. This process—operationalisation—makes variables specific and testable.
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Example: Instead of saying someone is “more talkative,” a better operationalised hypothesis would be:
“After drinking 300ml of SpeedUpp, participants say more words in the next five minutes than those who drink 300ml of water.”
Control of variables
Extraneous variable (EV) definition -
p. 168
Any variable other than the IV that could affect the DV if not controlled.
EVs are essentially nuisance variables that do not vary systematically with the IV, but can still influence results, making them potential sources of error.
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Control of variables
Confounding variables definition -
p. 168
Confounding variables are variables other than the IV that have affected the DV and vary systematically with the IV.
confounding variables make it unclear whether changes in the DV are due to the IV or the confounding variable.
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Control of variables
Demand characteristics definition -
p. 168
Cues from the researcher or research setting that may reveal the study’s purpose to Participants, potentially causing them to change their behaviour.
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Control of variables
Investigator effects definition -
p. 168
Any influence the researcher’s behaviour (intentional or unintentional) has on the outcome of the study. This can affect the DV and may occur through study design, participant selection, or interaction during the research.
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Control of variables
Randomisation definition -
p. 168
Using chance to reduce bias when designing a study, such as in the order of conditions, helping to ensure fair and unbiased results.
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Control of variables
Standardisation definition -
p. 168
The process of using the same procedures and instructions for all participants to ensure consistency and control in a research study.
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Control of variables
Extraneous variables (EV) in an experiment:
p. 168
EV’s potentially interfere with the IV or DV) so should be controlled or removed. When possible, they are identified at the start of the study by the researcher, who then takes steps to minimise their influence.
Many EV’s are straightforward to control e.g age of the Pp’s, the lighting in the lab, etc.
The EV is described as ‘nuisance variables’ because they do not confound the findings of the study but just make it harder to detect a result.
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