Question

Asked May 21, 2019

29 views

A simple random sample of n=23 professors at a local community college have a mean course evaluation score of 3.91 with a standard deviation of 0.53. Assuming that the distribution of course evaluation scores is normally distributed, test the claim that the mean course evaluation score is 4.00 for all professors at this community college using a 0.05 significance level.

Step 1

**Solution:**

**Null and alternative hypotheses:**

Null hypothesis: µ = 4

Alternative hypothesis: µ ≠ 4

**Test statistic:**

The population standard deviation is unknown and *n* < 30. Hence, the test statistic for this problem is shown below.

Step 2

**Calculation of test statistic value:**

Here, *x*-bar=3.91, *s*=0.53, *n*=23, µ = 4

Step 3

**Degrees of freedom:**

*df* = n – 1

= 23 – 1

= 22

**Rejection region for two-tailed test:**

Significance level is 0.05. the rejection region can be obtained using the EXCEL formula. “=T.INV.2T(0.05,22)”

Thus, the critical value of Student’s *t* is *t*tab= 2.07...

Tagged in

Find answers to questions asked by student like you

Show more Q&A

Q: Consider a drug that is used to help prevent blood clots in certain patients. In clinical trials, am...

A: Test statistic calculation:The test hypotheses are:Null hypothesis:H0: p = 0.03, that is, 3% in the ...

Q: Suppose x has a normal distribution with mean μ = 28 and standard deviation σ = 7.Describe the distr...

A: Note:Hi there! Thank you for posting the question. Your question asks about the “distribution of x v...

Q: Do heavier cars really use more gasoline? Suppose a car is chosen at random. Let x be the weight of ...

A: Hi, since the problem posted by you contains multiple sub-parts, we are answering the first three su...

Q: 1.) The mean monthly utility bill for a sample of households in a city is $178.95 with a standard de...

A: Mean utility bill, µ= $178.95Standard deviation, σ = $13.45

Q: The book states the following: "The smaller our sample size and the more extreme the outlier score i...

A: We know from equation 1 below that the width of confidence interval is inversely proportional to the...

Q: The results of a pre-test and a post-test for ten students is given below. Is there a significant di...

A: Denote µd as the median difference for post and pre-test.Hypotheses:Null hypothesis: The median diff...

Q: A study was conducted to see whether participants would ignore a sign that said, "Elevator may stick...

A: Explanation:Here, the experimenter controls the presence/absence of the confederates, as its effect ...

Q: For what types of data would you use nonparametric verses parametric statistic?

A: In hypothesis testing, the parametric tests are used to make inference on some unknown parameters ba...

Q: You are the foreman of the Bar-S cattle ranch in Colorado. A neighboring ranch has calves for sale, ...

A: Note: We are authorized to answer 3 sub parts at a time, since you have not mentioned which subparts...