Threats to Internal Validity

Question 1

A second variable that unitentionally varies systematically with the independent variable

Answer 1

design confound

Question 2

In an independent-groups design, when the two independent variable groups have systematically different kinds of participants in them

Answer 2

Selection effect

Question 3

In a repeated-measures designs, when the effect of the independent variable is confounded with carryover from one level to the other or with practice fatigue or boredom

Answer 3

Order effect

Question 4

An experimental group improves over time only because of natural development r spontaneous improvement

Answer 4

Maturation

Question 5

An experimental group changes over time because of an external factor that affects all of most members of the group

Answer 5

History

Question 6

An experimental group whose average is extremely low (or high) at pretest will get better (or worse) over time because the random events that caused the extreme pretest scores do not recur the same way at posttest

Answer 6

Regression to the Mean

Question 7

An experimental group changes over time, but only because the most extreme cases have systematically dropped out and their scores are not included in the posttest

Answer 7

Attrition

Question 8

A type of order effect: An experimental group changes over time because repeated testing has affected the participants. Practice effects (fatigue effects) are one subtype.

Answer 8

Testing

Question 9

An experimental group changes over time, but only because the measurement instrument has changed.

Answer 9

INstrumentation

Question 10

An experimental group’s ratings differ from a comparison group’s, but only because the researcher expects the groups’ ratings to differ.

Answer 10

Observer bias

Question 11

Participants guess what the study’s purpose is and change their behavior in the expected direction.

Answer 11

Demand characteristic

Question 12

Participants in an experimental group improve only becasue they believe in the efficacy of the therapy or drug they recieve.

Answer 12

Placebo effect

Question 13

Ex. If people who take notes on laptops answer harder question than those who take notes long hand

Answer 13

Design confound

Question 14

Ex. In the autism study, some parents insisted they wanted their children to be in the intensive treatment group rather than the control group

Answer 14

Selection effect

Question 15

Ex. People rated the shared chocolate higher only because the first taste of chocolate is always more delicious than the second one.

Answer 15

Order effect

Question 16

Ex. Disruptive boys settle down as they get used to the camp setting

Answer 16

Maturation

Question 17

Ex. Dorm residents use less air conditioning in November than september becasue the weather is cooler.

Answer 17

History

Question 18

Ex. A group’s average is extremely depressed at pretest, in part because some members volunteered for therapy when they were feeling much more depressed than usual

Answer 18

Regression to the mean

Question 19

Ex. Because the most rambunctious boy in the cabin leaves camp early, his unruly behavior affects the pretest mean but not the posttest mean.

Answer 19

Attrtion

Question 20

Ex GRE verbal scores improve only because students take the same version of the test both times and therefore are more practiced at posttest.

Answer 20

Testing

Question 21

Ex. Coders get more lenient over time, so the same behavior is coded as less distruptive at posstest than at pretest.

Answer 21

INstrumentation

Question 22

Ex The researcher expects a low sugar diet to decrease the campers unruly behavior, so he notices only calm behavior and ignores wild behavior.

Answer 22

Observer Bias

Question 23

Ex. Campers guess that the low sugar diet is supposed to make them calmer, so they change their behavior accordingly

Answer 23

Demand Characteristic

Question 24

Ex. Women receiving cognitive therapy improves simply because they believe the therapy will work for them.

Answer 24

Placebo Effect

Question 25

Q. Did the researcher turn potential third Variables into control variables

Answer 25

Design Confound

Question 26

Q. Did the researcher use random assignment or matched groups to equalize groups?

Answer 26

Selection effect

Question 27

Q. Did the researchers counterbalance the orders of presentation of the levels of independent variable?

Answer 27

Order effect

Question 28

Q. Did the researchers use a comparison group of boys who had an equal amount of time to mature but who did not receive the treatment?

Answer 28

Maturation

Question 29

Q. Did the researchers include a comparison group that had an equal exposure to the external factor but did not receive the treatment?

Answer 29

History

Question 30

Q. Did the researchers include a comparison group that was equally extreme at pretest but did not receive the therapy?

Answer 30

Regression to the mean

Question 31

Q. Did the researchers compute the prestest and posttest scores with only the ifinal sample included, removing any dropout/s data from the pretest group average?

Answer 31

Attrtion

Question 32

Q. Did the researchers have a comparison group take the same two tests? Did they use a posttest only design or did they use alternative forms of the measure for the pretest and posttest

Answer 32

Testing

Question 33

Q. Did the researchers train coders to use the same standards when coding? are pretest and posttest measures demonstrably equivalent?

Answer 33

INstrumentation

Question 34

Q. Were the observers of the dependent variable unaware of which condition participants were in?

Answer 34

Observer bias

Question 35

Q. Were the participants kept unaware of the purpose of the study> Was it an independent groups design which makes participants less able to guess the study/s purpose?

Answer 35

Demand characteristic

Question 36

Q. DId a comparison group recieve an inert drug/therpay

Answer 36

Placebo Effect