To study the effects of aging, Professor Drake compares the reaction times of 60-year-olds with those of 30-year-olds. She tests all younger subjects in the morning, and all older subjects in the afternoon.
She concludes that aging causes a decline in the speed of responses. This study lacks ________ because of potential ________.
A) external validity; demand characteristics
B) external validity; confounds
C) internal validity; demand characteristics
D) internal validity; confounds
Question 2
Which of the following could be considered a limitation to the experimental method?
A) The laboratory settings can be very artificial.
B) The researcher can't make causal statements.
C) The researcher has very little control over what happens in the study.
D) The researcher can't manipulate the independent variable.
The nitrogen cycle. Numbers represent fluxes as 1012 g N per year (data from Schlesinger 1991, after
Methane combustion as an energy–yielding redox reaction.
The explosion of the Maine in Havana harbor, killing 260 men, caused much speculation in the newspap
Study Duddy 1
Charlie Stone wants to retire in 30 years, and he wants to have an annuity of $1000 a year for ...
A field study of guppy life history evolution.