aims, hypotheses and variables

Question 1

what is the aim of a study?

Answer 1

a general statement covering the topic that will be investigated , identifying the purpose of the research

Question 2

how is an aim different from a hypothesis?

Answer 2

the aim is a general expression of what the researcher wants to find out, while a hypothesis is a specific, testable prediction

Question 3

give an example of an aim

Answer 3

‘to investigate the effects of caffeine on memory’

Question 4

what is a hypothesis?

Answer 4

a testable statement predicting what the research expects to find from the experiments

Question 5

what are the two types of hypotheses?

Answer 5

the null hypothesis (NH) and the alternative hypothesis (AH)

Question 6

what does an alternative hypothesis include?

Answer 6

it includes both the independent variable and the dependant variable, and these variables must be operationalised

Question 7

what does operationalising the independent variable involve?

Answer 7

specifying how the independent variable is manipulated (e.g drinking 200ml of caffeine vs 200ml of water)

Question 8

how is the dependant variable operationalised in a study?

Answer 8

by defining how the dependant variable is measured (e.g the number of correctly recalled items from a list of 15 words)

Question 9

what are the two types of alternative hypotheses?

Answer 9

directional (one-tailed) and non directional (two-tailed)

Question 10

what does a directional hypothesis predict?

Answer 10

the specific direction of the difference between conditions (e.g one condition will outperform the other)

Question 11

provide an example of a directional hypothesis

Answer 11

“participants who drink 200ml of caffeine before a memory test will recall more items than those who drink 200ml of water)

Question 12

what does a non-directional hypothesis predict?

Answer 12

it predicts that there will be a difference but does not specify the direction of the difference

Question 13

provide an example of a non-directional hypothesis

Answer 13

“there will be a difference in the number of correctly recalled items depending on whether participants drink caffeine or water”

Question 14

what is the null hypothesis?

Answer 14

it assumes that the independent variable will have no effect on the dependant variable

Question 15

why must all psychological research include a null hypothesis?

Answer 15

because it is the starting assumption until the experiments results indicate otherwise

Question 16

provide an example of a null hypothesis

Answer 16

“there will be no difference in the number of correctly recalled items depending on whether participants drink caffeine or water”

Question 17

what happens if the results show no difference between conditions?

Answer 17

the null hypothesis is accepted.

Question 18

what happens if the results show a difference between conditions?

Answer 18

the null hypothesis is rejected, and the alternative hypothesis is accepted.

Question 19

how are hypotheses for correlational investigations different from experimental hypotheses?

Answer 19

they use the term ‘relationship’ or ‘correlation’ instead of ‘difference’

Question 20

provide an example of a non directional hypothesis for a correlational study

Answer 20

“there will be a relationship between the number of cups of caffeine drunk and the number of hours slept per night”

Question 21

provide an example of a directional hypothesis for a correlational study

Answer 21

“there will be a negative relationship between the number of cups of caffeine drunk and the number if hours slept per night”

Question 22

provide an example of a null hypothesis for a correlational study

Answer 22

“there will be no relationship between the number of cups of caffeine drunk and the number of hours slept per night”