Deck 10: Experimental Designs

Question 1

A field study is an experiment done in the natural environment in which work goes on as usual,but treatments are given to one or more groups.

Answer 1

False

Question 2

A time series design thus allows the researcher to assess the impact of a treatment over time.

Answer 2

True

Question 3

History effects (the dropout of individuals from groups)is a problem for all experimental designs.

Answer 3

False

Question 4

One way of controlling "nuisance" variables is to match the various groups by picking the confounding characteristics and deliberately spreading them across groups.

Question 5

A Quasi-Experimental Design guarantees the maximum internal and external validity,ruling out many other rival hypotheses.

Question 6

External validity of lab experiments refers to the confidence we place in the cause-and-effect relationship.

Question 7

There is a trade-off between internal validity and external validity.If we want high internal validity,we should be willing to settle for lower external validity and vice versa.

Question 8

Biases that might affect the internal validity of experimental designs are often reduced by enhancing the level of sophistication of the experimental design.

Question 9

A Quasi-Experimental Design measures true cause-and-effect relationships.

Question 10

The manipulation of the independent variable is also known as the treatment,and the results of the treatment are called treatment effects.

Question 11

Internal validity refers to the extent of generalizability of the results of a causal study to other settings.

Question 12

Major threats to validity in a "pretest & posttest with one experimental group only" are:
a.History,maturation,main testing,interactive testing,mortality.
b.Statistical regression,maturation,main testing,interactive testing,mortality.
c.Statistical regression,instrumentation,main testing,interactive testing,mortality.
d.History,instrumentation,main testing,interactive testing,mortality.

Question 13

A key problem of time series is history: certain events or factors that have an impact on the independent variable-dependent variable relationship might unexpectedly occur while the experiment is in progress.

Question 14

Manipulation of independent variables in order to unravel causal relationships is unacceptable from a scientific point of view.

Question 15

Cause-and-effect inferences can be contaminated by the effects of the passage of time.Such contamination effects are denoted history effects.

Question 16

Quasi-Experimental Designs expose an experimental group to a treatment and measure its effects.

Question 17

An interactive testing effect occurs when the prior observation (the pretest)affects the later observation (the posttest).