Question

In: Statistics and Probability

I want you to conduct a hypothesis test for a difference of means for cholesterol levels...

I want you to conduct a hypothesis test for a difference of means for cholesterol levels between male and female students. There are 148 females and 164 males in our sample. You can treat this as a large sample problem and use z-values for confidence intervals and hypothesis tests (however, Excel uses a t-value in anything it calculates). The output from Microsoft Excel is given below to help. Your job will be to find the right numbers in the output to help solve the problem.

EXCEL DESCRIPTIVE STATISTICS FOR CHOLESTEROL LEVELS OF MALES AND FEMALES

Cholesterol	Females	Males
Mean	200.318	196.085
Standard Error	0.881	0.966
Median	201	196
Mode	194	196
Standard Deviation	10.721	12.372
Sample Variance	114.939	153.072
Kurtosis	-0.493	0.015
Skewness	-0.109	0.086
Range	47	61
Minimum	176	166
Maximum	223	227
Sum	29647	32158
Count	148	164
Confidence Level (95.0%)	1.742	1.908

2. The Descriptive Statistics are given above. Put a 95% Confidence Interval around just the female mean. What is the lower bound for the 95% CI? Use 3 significant decimal places and use the proper rules of rounding.

Expert Solution

1. We conduct a hypothesis test for a difference of means for cholesterol levels between male and female students. There are n_F = 148 females and n_M =164 males in our sample.

The null and alternative hypothesis is

Test statistic is

where

Test statistic value is

with degree of freedom is

p-value is 0.0013 with 310 degree of freedom for two tailed hypothesis

The p-value is less than level of significance (0.05). We reject the null hypothesis and conclude that there is a difference of means for cholesterol levels between male and female students.

2. 95% Confidence Interval around just the female mean

the lower bound for the 95% CI is 198.591

orchestra answered 2 years ago

Hypothesis Test for Difference in Population Means (σσ Unknown) You wish to test the following claim...

Hypothesis Test for Difference in Population Means (σσ Unknown) You wish to test the following claim (HaHa) at a significance level of α=0.10α=0.10. Ho:μ1=μ2Ho:μ1=μ2 Ha:μ1≠μ2Ha:μ1≠μ2 You believe both populations are normally distributed, but you do not know the standard deviations for either. We will assume that the population variances are not equal. You obtain a sample of size n1=14n1=14 with a mean of M1=78.1M1=78.1 and a standard deviation of SD1=5.6SD1=5.6 from the first population. You obtain a sample of size...

You want to test your hypothesis below: There is a difference in mean test scores between...

You want to test your hypothesis below: There is a difference in mean test scores between two classes: Class 1 vs. Class 2 Provide your answers in the template below the data set. class 1 class 2 15 15 23 12 22 17 18 17 19 19 18 17 15 17 19 18 16 13 21 20 15 19 14 21 20 21 23 14 19 19 17 17 17 17 21 18 7 13 16 20 14 19...

Two sample Independent t-test You want to test your hypothesis below: There is a difference in...

Two sample Independent t-test You want to test your hypothesis below: There is a difference in developing skills by practice methods: Distributed practice vs. Massed practice. Provide your answers in the template below the data set. distributed practice massed practice 17 19 18 20 16 22 18 24 12 10 20 25 18 20 20 22 20 21 22 23 20 20 10 10 8 12 12 14 16 12 16 20 18 22 20 24 18 23 21...

Hypothesis Testing and Confidence Intervals for Proportions and Hypothesis Test for Difference between Two Means A...

Hypothesis Testing and Confidence Intervals for Proportions and Hypothesis Test for Difference between Two Means A pharmaceutical company is testing a new cold medicine to determine if the drug has side affects. To test the drug, 8 patients are given the drug and 9 patients are given a placebo (sugar pill). The change in blood pressure after taking the pill was as follows: Given drug: 3 4 5 1 -2 3 5 6 Given placebo: 1 -1 2 7 2...

You want to do a difference in means test: H 0 : μ x − μ...

You want to do a difference in means test: H 0 : μ x − μ y = 0.

I want to test the hypothesis that a die is fair by rolling it over and...

I want to test the hypothesis that a die is fair by rolling it over and over, independently, until the third time I see any single number. I will conclude that the die is loaded (not fair) if it takes four or fewer rolls for any single number to come up three times. What is the significance level?

You will perform a Two Sample Hypothesis Test for Means. For the Hypothesis Tests, make sure...

You will perform a Two Sample Hypothesis Test for Means. For the Hypothesis Tests, make sure to report the following steps: Identify the null hypothesis, Ho, and the alternative hypothesis, Ha. Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed. Find the critical value(s) and identify the rejection region(s). Find the appropriate standardized test statistic. If convenient, use technology. Decide whether to reject or fail to reject the null hypothesis. Interpret the decision in the context of the original...

I want to conduct the following test at the α=0.01 level of significance by determining the...

I want to conduct the following test at the α=0.01 level of significance by determining the null and alternative hypotheses, the test statistic, and the p-value. These samples were obtained independently using simple random sampling. Test whether p1≠p2. Sample data are: x1=28, n1=255, x2=38, and n2=301

What is the difference between a test of independent means and a test of dependent means,...

What is the difference between a test of independent means and a test of dependent means, and when is each appropriate?

In a 2 sample test for a difference in means, if we fail to reject the null hypothesis, we conclude

In a 2 sample test for a difference in means, if we fail to reject the null hypothesis, we concludea. There is evidence that the 2 population means are equal to each otherb. There is evidence that the 2 sample means are equal to each otherc. There is evidence that the 2 population means are not equal to each otherd. There is evidence that the 2 sample means are not equal to each othere. There is no evidence that...