9.Patients who are addicted to cocaine are sometimes using the drug to combat depression. As such, sometimes addicts are given antidepressant medications to
prevent relapse. A three-year study compared the effects of two such medications,
lithium and desipramine, along with a placebo for 72 cocaine users wishing to break
the habit. The patients were put into 3 groups of 24, and given 1 of the 3 treatments at
random. This two-way table illustrates the results.
Treatment Relapse No relapse Total
Desipramine 10 14 24
Lithium 18 6 24
Placebo 20 4 24
Total 48 24 72
According to the table, 48 of the addicts relapsed regardless of the treatment given.
This number is an example of a
A. relative frequency
B. marginal frequency.
C. conditional relative frequency.
D. joint frequency