Math

StatisticsQ&A LibraryA psychologist is studying the self image of smokers, as measured by the self-image (SI) score from a personality inventory. She would like to examine themean SI score, µ, for the population of all smokers. Previously published studies have indicated that the mean SI score for the population of all smokers is 80and that the standard deviation is 10, but the psychologist believes that the value for the mean has decreased. She plans to perform a statistical test. She takesa random sample of SI scores for smokers and computes the sample mean to be 72.Based on this information, answer the questions below.What are the null hypothesis (H) and the alternative hypothesis (H,) that should be used for the test?H: µ is ?H: p is ?In the context of this test, what is a Type II error?A Type II error is ?fact, p is ?v the hypothesis that u is ?when, inSuppose that the psychologist decides not to reject the null hypothesis. What sort of error might she bemaking? ?Question

Asked Feb 17, 2020

60 views

An electronics manufacturing process has a scheduled mean completion time of

70

minutes. It is claimed that, under new management, the mean completion time,

μ

, is less than

70

minutes. To test this claim, a random sample of

20

completion times under new management was taken.

The sample had a mean completion time of

65

minutes and a standard deviation of

10

minutes. Assume that the population of completion times under new management is normally distributed. At the

0.05

level of significance, can it be concluded that the mean completion time,

μ

, under new management is less than the scheduled mean?

Perform a one-tailed test. Then fill in the table below.

Carry your intermediate computations to at least three decimal places and round your answers as specified in the table.

1 Rating

Step 1

Hey, since there are multiple questions posted, we will answer first question. If you want any specific question to be answered then please submit that question only or specify the question number in your message.

Step 2

Null hypothesis:

*µ=***70 .**

Alternative hypothesis:

*µ***<70.**

**This is a left tailed test.**

Since the population standard deviation is unknown, the appropriate test is **one sample t-test.**

Here, the sample mean, *x*-bar is 65.

Population mean, *µ* is 70.

Sample standard deviation, *s *= 10.

Sample size, *n* is 20.

The test statistic value can be obtained as follows:

...Tagged in

Find answers to questions asked by student like you

Show more Q&A

Q: Find the z score corresponding to a score of x =45 for each of the following distributions. (A) mean...

A: a). It is given that mean, µ is 40 and standard deviation, σ is 20. The value of score, x is 45. The...

Q: Dr. El-Saidi collected data on the number of hours spent by his 100 students over the weekend to pre...

A: Person mode of skewness: Skewness = 3(Mean-Median)/σ

Q: A researcher suspects that the actual prevalence of generalized anxiety among children and adolescen...

A: From the provided information, The sample size (n) = 98 Sample proportion (p) = 0.061 The hypotheses...

Q: Use the given data to find the minimum sample size required to estimate the population proportion. M...

A: Click to see the answer

Q: A hacker is trying to guess someone's password. The hacker knows (somehow) that the password is 4 di...

A: The probability that the hacker guesses the password on her first try is,

Q: Javier volunteers in community events each month. He does not do more than five events in a month. H...

A: The probability distribution representing the number of volunteers X made by Javier in a month is, ...

Q: Assume that when adults with smartphones are randomly selected, 39% use them in meetings or classe...

A: Define the random variable x as the number of adults using smartphones in meetings or classes. Here,...

Q: A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of...

A: Note: As per honor code policy, we can answer only 3 sub parts at a time. So we are answering the fi...

Q: 1E(X; – Xn)². Prove 1. Let X1,..., Xm,... - iid N(u, T) and consider the MLE în that î, is a consist...

A: Given X1, X2, … Xn iid N(µ, τ) Given MLE