Research Methods- Experimental method Flashcards
Experimental method -
Involves the manipulation of an independent variable to measure the effect on the dependent variable. Experiments may be laboratory, field, natural or quasi.
Aim -
A general statement of what the researcher intends to investigate; the purpose of the study.
Hypothesis -
A clear, precise, testable statement that states the relationship between the variables to be investigated. Stated at the outset of any study.
Directional hypothesis -
States the direction of the difference or relationship.
Non-directional hypothesis -
Does not state the direction.
Variables -
Any ‘thing’ that can vary or change within an investigation. Variables are generally used in experiments to determine if changes in one thing result in changes to another.
Independent variable (IV) -
Some aspect of the experimental situation that is manipulated by the researcher - or changes naturally - so the effect on the DV can be measured.
Dependent variable (DV) -
The variable that is measured by the researcher. Any effect on the DV should be caused by the change in the IV
Operationalisation -
Clearly defining variables in terms of how they can be measured.
What is the aim of the investigation based on the energy drink theory?
To investigate whether drinking energy drinks makes people more talkative.
What is a hypothesis in psychological research?
A hypothesis is a statement made at the start of a study that clearly states the relationship between variables as stated by the theory.
What is the hypothesis for the energy drink investigation?
Drinking SpeedUpp causes people to become more talkative.
What is a directional hypothesis?
A directional hypothesis specifies the expected difference between conditions or groups, using terms like more, less, higher, lower, faster, or slower.
Provide an example of a non-directional hypothesis for the energy drink study.
People who drink SpeedUpp differ in terms of talkativeness compared with people who don’t drink SpeedUpp.
Provide an example of a directional hypothesis for the energy drink study.
People who drink SpeedUpp become more talkative than people who don’t.
What is a non-directional hypothesis?
A non-directional hypothesis states that there is a difference between conditions or groups but does not specify the nature of the difference.
How do psychologists decide whether to use a directional or non-directional hypothesis?
Psychologists use a directional hypothesis when previous research suggests a particular outcome and a non-directional hypothesis when there is no previous research or findings are contradictory.
Why is a directional hypothesis chosen for the energy drink study?
Because the effects of caffeine and sugar on talkativeness are well-documented, even though SpeedUpp is a new energy drink.
What are independent and dependent variables in an experiment?
The independent variable (IV) is what the researcher manipulates, and the dependent variable (DV) is what the researcher measures to see the effect of the IV.
What is the IV in the energy drink experiment?
The IV is whether participants drink SpeedUpp or water.
What is the DV in the energy drink experiment?
The DV is the number of words participants say in a five-minute period after drinking.
What are the two levels of the IV in the energy drink experiment?
The two levels are the control condition (no SpeedUpp / drink of water) and the experimental condition (energy drink).
What is operationalisation of variables?
Operationalisation is defining variables in a way that makes them clear, measurable, and testable.
How are the variables operationalised in the improved hypothesis for the energy drink study?
Participants drink 300ml of SpeedUpp or 300ml of water, and talkativeness is measured by the number of words spoken in the next five minutes.
What is the improved directional hypothesis for the energy drink study?
After drinking 300ml of SpeedUpp, participants say more words in the next five minutes than participants who drink 300ml of water.
What is the purpose of keeping other variables constant in an experiment?
To ensure that any effect on the DV is caused by the IV alone and not by other factors.
What is the control condition in the energy drink experiment?
The control condition is when participants drink water instead of SpeedUpp.
What is the experimental condition in the energy drink experiment?
The experimental condition is when participants drink SpeedUpp.
What is the main challenge in conducting the energy drink experiment?
Counting all the words that twenty participants say in a five-minute period.
