**Does Caffeine Improve Exam Performance?**Suppose all students in the 8:30 section of a course are given a "treatment" (two cups of coffee) and all students in the 9:30 section are not permitted to have any caffeine before a mid-term exam.Instead of the original plan, students in both sections are randomly assigned to a group receiving two cups of caffeinated coffee, a group receiving two cups of decaffeinated coffee, or a group receiving no beverage at all. The coffee is so bad that students cannot tell whether they are enjoying caffeine or decaf, but as it turns out, both groups receiving coffee did better on the exam than students in the group who were not given anything.This could be the result of:- ○ an observational study.- ○ the placebo effect.- ○ voluntary response.- ○ sampling variability.

A placebo is a kind of pseudo treatment that is given to a group of sample points in place of the…

Answered: Does caffeine improve exam performance?…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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3. Bayesian Inference A cab was involved at night in a hit and run accident. In this town there are only two cab companies, the Blue with 80% of the cabs and the Green company with the remaining 20%. As it happened there was a witness to the accident who identified the hit and run cab as Blue. The case came to trial. An important part of the testimony was a test of the reliability of the eyewitness to identify a cab as being either Blue or Green under the same circumstances as those that existed the night of the accident. The result of these tests was that the witness correctly identified a blue cab as blue 70% of the time and a green cab as green 80% of the time. On the basis of the claim of the eyewitness and the test conducted by the court, what is the probability that the cab involved in the accident was in fact Blue as the witness had claimed?
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