Pre-experimental designs produce the greatest threat to internal and external validity because it provides
a. either no control group or no way to equate the groups used
b. a control group through randomization
c. an equivalent-groups design
d. none of the above
Question 2
It is generally inappropriate to generalize the results of a study to a population when the subjects are NOT
randomly selected from the population because
a. the number of subjects in the study is too small
b. there is likely experimenter bias
c. there is little assurance that the subjects are an adequate representation of the population
d. there is little assurance that the data collected from the subjects is reliable
Experimental evidence of the effect of allelochemicals on plant production.
The kidney. Illustration of a sectioned kidney, which reveals its internal features.
Diverticulosis. It is the presence of abnormal pouches in the wall of the large intestine (diverticu
(a) Blue arrows (right side): External components of the innate immune system: human body with skin, ...
The Tsunami Threat in Japan
Internal Renal Anatomy