Access PsychologyHannah Butlerhbutler@stvincent.ac.uk

Variables

What did you discover??

Independent variables•"Why is the independent variable labelled

the independent variable? Because it is independent of research participants' actions - participants have no control over what condition or group they are assigned to. It is the experimenter who manipulates the independent variable, whereas participants have nothing to do with it (they are simply exposed to one version of the independent variable)."(Breckler, Olson, & Wiggins, 2006)

Independent variables•The independent variable is the

characteristic of a psychology experiment that is manipulated or changed.

•For example, in an experiment looking at the effects of studying on test scores, studying would be the independent variable.

•Researchers are trying to determine if changes to the independent variable (studying) result in significant changes to the dependent variable (the test results).

Putting it into practise •A researcher wants to determine if the

colour of an office has any effect on worker productivity. In an experiment, one group performs a task in a yellow room while another performs the same task in a blue room.

• In this example, the colour of the office is the independent variable.

•A business wants to determine if giving employees more control over how to do their work leads to increased job satisfaction.

• In an experiment, one group of workers is given a great deal of input in how they perform their work, while the other group is not.

•The amount of input the workers have over their work is the independent variable in this example.

•Educators are interested in whether participating in after-school math tutoring can increase scores on standardized math exams.

• In an experiment, one group of students attends an after-school tutoring session twice a week while another group of students does not receive this additional assistance.

•What is the independent variable?

• In this case, participation in an after-school math tutoring is the independent variable.

•Researchers want to determine if a new type of treatment will lead to a reduction in anxiety for patients suffering from social phobia.

• In an experiment, some volunteers receive the new treatment, another group receives a different treatment, and a third group receives no treatment.

•What is the independent variable?

•The independent variable in this example is the type of therapy

Dependant variables•"In psychology studies, the dependent

variable is usually a measurement of some aspect of the participants' behaviour. The independent variable is called independent because it is free to be varied by the experimenter. The dependent variable is called dependent because it is thought to depend (at least in part) on the manipulations of the independent variable."(Weiten, 2013)

Dependant variables

•The dependent variable is the variable that is being measured in an experiment.

•For example, in a study looking at how tutoring impacts test scores, the dependent variable would be the participants' test scores.

• In a psychology experiment, researchers are looking at how changes in the independent variable cause changes in the dependent variable.

•One way to help identify the dependent variable is to remember that it depends on the independent variable.

•When researchers make changes to the independent variable, they then measure any resulting changes to the dependent variable.

Putting it into practise•Researchers want to discover if listening to

classical music helps students earn better grades on a math exam.

• In this example, the scores on the math exams are the dependent variable.

•Researchers are interested in seeing how long it takes people to respond to different sounds.

• In this example, the length of time it takes participants to respond to a sound is the dependent variable.

•Researchers want to know whether first-born children learn to speak at a younger age than second-born children.

•What is the dependant variable?

• the dependent variable is the age at which the child learns to speak.

•Researchers are interested in seeing how long it takes people to respond to different sounds.

•What is the dependant variable?

• In this example, the length of time it takes participants to respond to a sound is the dependent variable.

Applying this knowledge to studies you know

•Pavlov•Milgram•Harlow

Pavlov• Just to recap…..• Physiologist Ivan Pavlov studied the digestive processes

of dogs, eventually winning the Nobel Prize for his research.

• Pavlov discovered that dogs would salivate even without a physiological reason, such as presence of food.

• He learned that dogs could be conditioned to salivate based on the presence of a certain stimulus.

• When dogs salivated because of the presence of food it was called a physiological response.

• When dogs salivated because of the presence of the lab worker's white coats it was called a learned response.

• He proved that a metronome could become the conditioned stimulus.

• What is the IV and DV?

•The metronome was the independent variable and the act of being fed was the dependent variable

Milgram• Just to recap….• Stanley Milgram performed an experiment with 40 male

volunteers acting as teachers. • The men sat in front of a series of switches and were told that if

they pressed the switches then shocks were delivered in various strengths to students on the opposite side of the glass.

• The switches were labelled with different strength intensities but they did not really give off shocks.

• The teachers were instructed to deliver shocks every time a student gave an incorrect answer.

• As the experiment progressed the students were told to deliver stronger and stronger shocks and the students reacted as if in great pain.

• The teachers continued to shock the students simply because they were directed to do so by a person in authority.

• What is the IV and DV?

•The independent variables were the statements made by the authority figure instructing the teacher to continue shocking.

•The dependent variable was the intensity of the shocks given.

Harlow•Harry Harlow tested the effect of love

using monkeys in what was called the Rhesus Monkey Love Experiments.

• In one experiment monkeys were taken from their mothers as infants and assigned a cloth and wire mother.

•The monkeys preferred the cloth mother leading Harlow to explain that they were attracted to contact comfort.

•What is the DV and the IV?

•The dependent variable was the choice made by the monkeys.

•The independent variable was the contact comfort- wire versus cloth.