Neonatal mortality has ______ across ethnic groups in the United States since 1980

If the air puff apparatus is turned off, _______ will occur

(a) generalization (b) operant regression (c) regression to the mean (d) extinction (e) a discriminative stimulus will appear

In experimental research, the variable that is systematically manipulated by the researcher is called the

a. positive variable b. extraneous variable c. dependent variable d. independent variable