On Question 1, assume we are conducting the z-test with a p-level of 0.05. Thus,
ID: 3204729 • Letter: O
Question
On Question 1, assume we are conducting the z-test with a p-level of 0.05. Thus, you need to get a z-value of 1.96 to say that we have a statistically significant result. Typically, if no p-value is given, you should assume the critical p-value is 0.05.
Reminder: the z-value of 1.96 corresponds to a percentage of 47.5% on Table A in Tanner. This means that between the center of the distribution and the z-value of 1.96, 47.5% of the distribution is covered. So, 2.5% of the distribution is left in the tail. If our p-value is set at 0.05, this means we will only reject the null hypothesis when we think our sample fell in the extreme 5% of the population distribution. Thus, if our population falls in the upper 2.5% or the lower 2.5%, then we reject null and say we have a statistically significant result.
EDUC 15: Problem Set 3 This problem set is due in class on Tuesday, February 7. Legibly write your name (or your group member's names at the top of each page. Fill in your answers in the spaces provided. If you need more room, attach and clearly label an extra sheet to this document When appropriate, show your work! 1. (10 points) The personnel director of UCI school of Education determines the keyboarding speeds of a random sample of secretaries from her school. She wishes to test the hypothesis that the mean for her population is equal to 50 words per minute (ku 50), the national mean for secretaries. The personnel director obtained a mean M 48 words per minute based on a sample of size 36. Further, she knows that the standard deviation of keyboarding speeds is 10 (o 100. She wishes to use the criterion of a level of significance p-0.05 A. State the null hypothesis and alternative hypothesis for this problem (both in symbols and in words, no more than 2 sentences) B. Explain in your own words what a level of significance of p 0.05 means. Think about the underlying distributions implied by Ho and Ha. LIMIT YOUR RESPONSE TO NO MORE THAN 3 SENTENCES. C. Calculate the standard error of the mean (om). SHOW YOUR WORK. D. Calculate the value of the z test. SHOW YOUR WORK. E. Explain the decision or conclusion that the personnel director would make. LIMIT YOUR RESPONSE TO NO MORE THAN TWO SENTENCES.Explanation / Answer
A. H0: mu=50 vs H1:mu not equal to 50
B. For a significance level of 0.05, expect to obtain sample means in the critical region 5% of the time when the null hypothesis is true. In these cases, you won't know that the null hypothesis is true but you'll reject it because the sample mean falls in the critical region.
C. Standard error = sd/sqrt (n)=10/6=1.67
D. z test =xbar-mu/standard error=48-50/1.67=-1.198
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.