Slides 3

Question 1

construct validity

Answer 1

the extent to which a measure can assess the construct of interest

Question 2

how to test construct validity

Answer 2

correlations between related constructs

Question 3

what does construct validity mean in an experimental context

Answer 3

what is actually driving the effects we are seeing in the experiment (assuming we have internal validity)

Question 4

major threats to construct validity

Answer 4

placebo and participant expectancy - especially if the participant believes the treatment will be good

Question 5

what is an active placebo

Answer 5

a pacebo that produces some of the somatic effects, mimicking the side effects of the actual treatment, but with no activity ingredient to remedy anything

Question 6

single-operational/narrow stimulus sampling

• what is it
• what is it a threat to

Answer 6

it is when there is another factor that participants may be responding to other than the treatment. For example a therapist if the therapist is there for all of the experimental participants it could be that the therapist is really good rather than if the type of therapy worked.
- threat to construct validity

Question 7

what are demand characteristics

Answer 7

cues of the situation associated with the study that seem incidental but may account for the results

• often happens during the informed consent process

Question 8

statistical conclusion validity:

Answer 8

the extent to which the analysis preformed enables one to draw correct inferences about the phenomena of interest

Question 9

state some threats to statistical conclusion validity

Answer 9

low power (small N, small effect size)

variability in procedures –> increases error in measurments

subject heterogeneity

unreliable measures

multiple comparisons

Question 10

definition of concept: alpha

Answer 10

the probability of rejecting a hypothesis when that hypothesis is true

also called type 1 error

Question 11

definition of concept: beta

Answer 11

the probability of accepting a hypothesis when it is false

also referred to as type II error

Question 12

definition of concept: power

Answer 12

the likelihood of finding differences between conditions when in fact, the conditions are truly difference

also defined as 1-beta

Question 13

effect size

Answer 13

a way of expressing the magnitude of the difference between conditions in terms of a common metric across measures and studies

Question 14

what happens to the effect size when there are more methological problems in the study

Answer 14

the effect size gets smaller (even if in nature, the effect size is large)

Question 15

effect size can be impact in two general ways:

Answer 15

1) increasing the difference between means

2) reducing the standard deviation by controlling for methological factors that increase variance

Question 16

threats to data-evaluation validity

Answer 16

several facets of the results and statistical evaluation that can obscure interpretation of the experiment

Question 17

kinds of threats to data evaluation validity

Answer 17

variability in procedures

unreliability of measurement

restricted range of measures - can’t show all group differences

multiple comparisons and error rates - when more stat tests are run, the likelihood of finding a “chance” finding is increased

Question 18

how to increase range of individuals from whom volunteering is sought

Answer 18

target individuals instead of general volunteer inquiries

helps entice individuals to volunteer from the age groups you want

Question 19

______ : who remains in the study after dropouts

Answer 19

attrition

Question 20

ways to combat attrition if you are planning a study

Answer 20

backload money (frowned on)
- more ethically acceptable is a completion bonus

target individuals who are less likely to back out
- not good for external validity

Question 21

describe the good subject

Answer 21

attempts to provide responses/behaviours that will corroborate their perceptions of investigator’s hypothesis

Question 22

explain the negativistic subject

Answer 22

attempts to provide response that will refute the investigates hypothesis, or provide no use

Question 23

the faithful subject

Answer 23

attempts to follow experimental protocal carefully and avoid acting on beliefs about studys purpose

Question 24

explain the apprehensive subject

Answer 24

when participant is concerned that their performance will be used to evaluate abilities, personality characteristics
- motivated to present sefl in most desirable light

Question 25

best defences against the different types of subjects

Answer 25

make sure they know enough to make an informed choice, but not enough to know the hypothesis
-to do this you could include more details than necessary/ in study so they don’t know what is involved I the study

Question 26

what is something that is often overlooked when collecting data even on huge research projects

Answer 26

data errors

Question 27

what is something like the file drawer effect that leaves information collected during a study out

Answer 27

selective reporting of results

Question 28

file drawer problem - why does it happen?

Answer 28

bias towards publishing significant effects

Question 29

selection biases

Answer 29

convenience samples and volunteers - over representation of undergrad psychology students - the majority of which are female -
- may select certain types of convenience or volunteer samples to answer certain questions

• highly educated, middle class, high IQ, sociable ppl with females , young, and jewish ppl volunteering the most

Question 30

what is reactivity

Answer 30

Reactivity of experimental arrangements
Awareness of being in a study may affect behaviour or elicit certain reactions
Usually increase productivity, performance
May not generalize to situations where you don’t feel like you’re being watched or you’re being monitored