In the computer game World of Warcraft, some of the strikes are critical strikes
ID: 3261607 • Letter: I
Question
In the computer game World of Warcraft, some of the strikes are critical strikes, which do more damage. Assume that the probability of a critical strike is the same for every attack, and that attacks are independent. During a particular fight, a character has 211 critical strikes out of 746 attacks. What is the lower bound for the 99% confidence interval for the proportion of strikes that are critical strikes. Round to three decimal places (for example: 0.419). Write only a number as your answer. Your Answer: AnswerExplanation / Answer
We can used one sample proportion z test.
Using minitab.
The command for one sample proportion z test in minitab is
Stat>>>Basic statistics>>>1-proportion...
Then click on summarized data
number of events = x = 211
Number of trials = n = 746
then click on option
Level of confidence in percentage = c = ( 1- lpha)*100 = = (1 -0.05)*100 = 99.0
so put "Confidence level " = 99.0
Alternative = not equal
then click on "Use test and interval based on normal approximation"
Then click on OK and again click on OK
So we get the following output
MTB > POne 746 211;
SUBC> Confidence 99;
SUBC> UseZ.
Test and CI for One Proportion
Sample X N Sample p 99% CI
1 211 746 0.282842 (0.240367, 0.325316)
Using the normal approximation.
Lower limit for 99% confidence interval for proportion of strikes that are critical strikes = 0.240