Week 8

Question 1

lab experiments

Answer 1

Take place in lab or controlled environment
Allows us to maximise control
Disadvantage: by maximising control, the researcher may create an artificial environment that may unduly influence the cause and effect relationship that the researcher is interested in

Question 2

field experiments

Answer 2

Natural setting
IV manipulated by researcher but not with as much control as in lab
Advantage: far less artificial than the lab

Question 3

between subjects design

Answer 3

each participant is measured under only one condition

Question 4

within subjects design

Answer 4

each participant is measured under two or more conditions

Question 5

matched-subjects design

Answer 5

each participant is measured under only one condition but is matched to subjects in the other condition based on certain characteristics

Question 6

quasi experimental

Answer 6

Researcher is still comparing two or more groups, but this time they are naturally occurring groups and thus there is no true manipulation of the IV, nor is there random allocation of participants into each group
Attempts to achieve same goal as the experimental strategy, but without random assignment
Hard to establish that changes in the DV are actually caused by changes in the IV

Question 7

types of quasi experimental

Answer 7

single group post test only
single group pretest/posttest
single group time series
nonequivalent control group posttest only
nonequivalent control group pretest/posttest design
multiple group time series

Question 8

single group posttest only

Answer 8

Single group of participants given a treatment/intervention and then tested
Weakest type as it lacks a control or comparison group

Question 9

single group pretest/posttest

Answer 9

Single group of participants take a pretest, then are given a treatment/intervention, before being tested again
Slightly stronger as there is now a control and treatment condition to compare
Order effect are difficult to combat with the use of counterbalancing because once the treatment group has been exposed to the intervention, they cannot go back to being ‘untreated’

Question 10

single group time series

Answer 10

single group of participants are measured repeatedly before and after a particular treatment/intervention
Allows us to see whether the behaviour being measured is stable before the intervention and whether it changes or not across multiple time points after the treatment/intervention

Question 11

nonequivalent control group posttest only

Answer 11

At least two nonequivalent groups are given an intervention, and then a post-test measure
There is now a comparison group added, but the control group is specified as nonequivalent because participants are not randomly assigned to either groups

Question 12

nonequivalent control group pretest/posttest

Answer 12

At least two nonequivalent groups take a pretest, then are given an intervention before being tested again
There is now a comparison group added but is species as nonequivalent because participants are not randomly assigned to either experimental or control group
Due to lack of random assignment of participants or controlling variables, the researchers cannot be confident that the groups are equivalent

Question 13

multiple group time series

Answer 13

Series of measures are taken on two or more groups, both before and after a treatment
Allows us to see whether the behaviour being measured is stable before the intervention, and whether is changes or not across multiple time points after the intervention
Also allows us to compare this between different groups to see whether the observed changes are consistent regardless of the group
Still subject to confounding variables

Question 14

internal validity

Answer 14

if a research study is able to show that changes in the IV lead to changes in the DV (with no alternative variable) then it is said to have high internal validity
If there are alternative explanations then it has low internal validity

Question 15

external validity

Answer 15

extent to which study findings are generalisable to populations other than the one from which participants have been drawn, as well as to other conditions and situations

Question 16

three types of generalisability which may be of concern

Answer 16

1. How well a sample generalises to the population
   Threatened by selection bias, use of college students or volunteer participants, participant characteristics, or the involvement of a different species
2. How well the findings of one research study generalise to another research study
   Threatened by novelty effects, multiple treatment interference, experimenter characteristics, assessment sensitisation, different measurement procedures, and time of measurement
3. How well the research study findings generalise to the real world
   Threatened by any of the aforementioned issues, as well as by the particular setting of the research

Question 17

threats to internal validity

Answer 17

subject effect 
history effect 
maturation effect 
experimenter effect 
testing effect 
regression to the mean 
ceiling effect 
instrumentation effect 
mortality (attrition) 
diffusion of treatment 
floor effect

Question 18

subject effect

Answer 18

threat in which the subject, consciously or unconsciously, affects the results of the study

Question 19

history effect

Answer 19

outside event that is not part of the manipulation of the experiment could be responsible for the results

Question 20

maturation effect

Answer 20

naturally occurring changes within the subjects could be responsible for the observed results

Question 21

experimenter effect

Answer 21

experimenter, consciously or unconsciously, affects the results of the study

Question 22

testing effect

Answer 22

repeated testing leads to better or worse scores

Question 23

regression to the mean

Answer 23

extreme scores, upon retesting, tend to be less extreme, moving towards the mean

Question 24

ceiling effect

Answer 24

limitation of the measuring instrument that decreases its capability to differentiate between scores at the top of the scale

Question 25

instrumentation effect

Answer 25

changes in the dependent variable may be due to changes in the measuring device

Question 26

mortality (attrition)

Answer 26

differential dropout rates may be observed in the experimental and control groups, leading to inequality between the groups

Question 27

diffusion of treatment

Answer 27

observed changes in the behaviours or responses of subjects may be due information received from other subjects in the study

Question 28

floor effect

Answer 28

limitation of the measuring instrument that decreases its capability to differentiate between scores at the bottom of the scale

Question 29

threats to external validity

Answer 29

interaction of causal effects with units
interaction of the causal effect over variations
interaction of the causal effect with outcome
interaction of causal effect with settings

Question 30

interaction of causal effect with units

Answer 30

causal effect in one type of unit may not apply to another type

Question 31

interaction of causal effect over variations

Answer 31

an effect for one condition/treatment may not hold when it is varied or combined with other treatments

Question 32

interaction of causal effect with outcome

Answer 32

causal effects may not apply to other types of outcomes

Question 33

interaction of causal effect with settings

Answer 33

causal effect in one setting may not generalise to other settings

Question 34

characteristics that differentiate experiments from other types of research studies

Answer 34

manipulation

control

Question 35

Research typically uses three basic techniques to control other variables:

Answer 35

Random assignment: distributes participant characteristics; controls environmental variables
Matching
Holding variables constant: using only specific age group and gender in research to hold age and gender constant

Question 36

posttest only control group design

Answer 36

an experimental design in which the dependent variable is measured after the manipulation of the independent variable

Question 37

pretest/posttest control group design

Answer 37

DV is measured both before and after manipulation of the IV

Question 38

solomon four group design

Answer 38

a design with four groups that is a combination of the post-test only control group design and the pretest/posttest control group design

Question 39

demand characteristics

Answer 39

subjects try to guess what characteristics the experimenter is in effect ‘demanding’

Question 40

Hawthorne effect

Answer 40

type of reactivity in which subjects improve or change an aspect of their behaviour because they know that they are being studied, rather than in response to the experimental manipulation

Question 41

college sophomore problem

Answer 41

external validity problem from using mainly college sophomores as subject in research studies; response to criticism:
Using them as subjects in a study does not negate the findings of the study
In the research conducted in many areas of psychology, the college sophomore problem is not an issue
Population of college students today is varied

Question 42

correlated groups design

Answer 42

subjects in the experiment and control groups are related in some way

Question 43

counterbalancing

Answer 43

mechanism for controlling order effects either by including all orders of treatment presentation or by randomly determining the order for each subject

Question 44

latin square

Answer 44

counter balancing technique to control for order effects without using all possible orders
Have the same number of orders as we do conditions

Question 45

carryover effects

Answer 45

a type of testing effect often present in within-subjects designs in which subjects ‘carry’ something with them from one direction to another

Question 46

sequential design

Answer 46

Developmental design that is a combination of cross sectional and longitudinal designs
Researcher begins with participant of different ages and tests them, later they retest the same individuals