Experimental studies utilize blinding to prevent researchers from biasing their measurements of the patients. But can they guess the treatment? In a study of a psychotherapeutic intervention, clinicians who were blinded were asked to guess what treatment their patients received. Data from that experiment are shown below. Assume that these data are indicative of the population of these treatments.
a) What is the probability that a correct guess is made for a randomly chosen subject?
b) If a randomly chosen subject received the placebo, what is the probability that the researcher correctly guesses the treatment?

Question

Experimental studies utilize blinding to prevent researchers from biasing their measurements of the patients. But can they guess the treatment? In a study of a psychotherapeutic intervention, clinicians who were blinded were asked to guess what treatment their patients received. Data from that experiment are shown below. Assume that these data are indicative of the population of these treatments.  ​ 
a) What is the probability that a correct guess is made for a randomly chosen subject? 
b) If a randomly chosen subject received the placebo, what is the probability that the researcher correctly guesses the treatment?

Quizplus · Accepted Answer

The Answer of Experimental studies utilize blinding to prevent researchers from biasing their measurements of the patients. But can they guess the treatment? In a study of a psychotherapeutic intervention, clinicians who were blinded were asked to guess what treatment their patients received. Data from that experiment are shown below. Assume that these data are indicative of the population of these treatments.  ​ 
a) What is the probability that a correct guess is made for a randomly chosen subject? 
b) If a randomly chosen subject received the placebo, what is the probability that the researcher correctly guesses the treatment?

Experimental Studies Utilize Blinding to Prevent Researchers from Biasing Their