operationalisation of variables

Question 1

what is operationalisation

Answer 1

defining a variable so it can be manipulated (IV) and measured (DV)

Question 2

what is an aim

Answer 2

• the general purpose
• usually more general than the hypothesis
• help to explain reasons for investigator deciding to test some specific hypotheses
• aim tells us why a given study is being carried out

Question 3

what is the hypothesus

Answer 3

• a precise, testable statement or prediction about the expected outcome of an investigation
• tells us what findings the experimenter expects will happen in the study

Question 4

what is a null hypothesis

Answer 4

• one that states results could be due to chance and are not significant in terms of supporting the idea being investigated
• sometimes its easier to state the null hypothesis in relation to group differences
• we need a null hypothesis for precision and proof

Question 5

what is an alternative/experimental hypothesis?

Answer 5

• a prediction or forecast of what the researcher thinks will happen to the dependent variable when the independent variable changes
• general term (alternative) refers to all hypotheses that are not the null hypothesis
• if the experimental method is being used it can also be referred to as an experimental hypothesis

Question 6

what is a directional (one-tailed) hypothesis

Answer 6

• a hypothesis might predict that instead of saying there will be a difference between groups in the amount they remember, you predict which group will remember most
• often used when previous research findings suggest which way the results will go
• “those in the loud noise condition will be able to remember less information from the textbook”
• predicted

Question 7

What is a non-directional (two tailed) hypothesis

Answer 7

• the direction of results is not predicted
• e.g. you may predict a differences between groups but have no idea which way the differences will fall
• “loud noise will have an effect on people’s ability to learn information from a textbook”

Question 8

what is a variable?

Answer 8

something that varies

in an experiment there will be two variables - the one manipulated by experimenter and one affected by changes

Question 9

what is the dependent variable

Answer 9

variable affected by changes in IV

variable measured

Question 10

what is the independent variable

Answer 10

• the variable directly manipulated by the experimenter
• e.g. ‘whether or not a revision guide is used’-directly under the control of the researcher
• the experimenter will decided whether or not the IV has caused a change in the DV
• IV is CHANGED

Question 11

what is a controlled variable

Answer 11

• ones that stay the same
• other variables than IV and DV must aim to be controlled so we can assume the only variable causing the change in the DV is the IV
• e.g. Baddeley had to make sure word lists in all conditions had words of the similar length, frequency of occurrence in the language etc

Question 12

what is a controlled variable

Answer 12

• ones that stay the same
• other variables than IV and DV must aim to be controlled so we can assume the only variable causing the change in the DV is the IV
• e.g. Baddeley had to make sure word lists in all conditions had words of the similar length, frequency of occurrence in the language etc

Question 13

what are extraneous variables?

Answer 13

• variables other than the IV and DV in an experimental condition
• they can get in the way of the link between the IV and DV unless acknowledges
• they must be controlled otherwise they run into the risk of becoming confounding variables-the effect they have on the DV confounds the accuracy of the data