Dean of students affairs at ACME University wants to make a…

Dean of students affairs at ACME University wants to make a CI for the proportion of students who cheat.  What is the minimum sample size required to do this if the width of the interval is to be no more than 0.04 and she thinks the students fairly honest, and that probably no more than 8% really cheat.

A political scientist is studying the impact of a political…

A political scientist is studying the impact of a political debate between candidates for governor in small western states. The scientist wants to evaluate the proportion of registered voters who switch their preference after viewing the debate. The following table contain the data from 75 registered voters. PreferenceBefore Debate PreferenceAfter Debate Total(Before Debate) Candidate A  Candidate B Candidate A  30 11 41 Candidate B 4 30 34 Total(After Debate) 34 41 75 At alpha=0.05 do we have enough evidence to conclude that lower proportion of people like candidate A after the debate compared to the proportion of people who liked candidate A before the debate.

In a campus volunteer group, adults 21 and older volunteer f…

In a campus volunteer group, adults 21 and older volunteer from one to nine hours each week to spend time with a disabled senior citizen. The program recruits among students, faculty, and staff of the university. The table below is a sample of the adult volunteers and the number of hours they volunteer per week. Volunteer Group Volunteer Hours Total 1-3 Hours 4-6 Hours 7-9 Hours Students 111 96 48 255 Faculty 96 133 61 290 Staff 91 150 53 294 Total 298 379 162 839 What test can be used to test if the number of hours volunteered is independent of the volunteer group? 

A political scientist is studying the impact of a political…

A political scientist is studying the impact of a political debate between candidates for governor in small western states. The scientist wants to evaluate the proportion of registered voters who switch their preference after viewing the debate. The following table contain the data from 75 registered voters. PreferenceBefore Debate PreferenceAfter Debate Total(Before Debate) Candidate A  Candidate B Candidate A  30 11 41 Candidate B 4 30 34 Total(After Debate) 34 41 75 We are interested in testing whether lower proportion of people like candidate A after the debate compared to the proportion of people who liked candidate A before the debate. the test statistic and the p-value are given as: