A simple random sample of size

nequals=8181

is obtained from a population with

mu equals 73μ=73

and

sigma equals 18σ=18.

​(a) Describe the sampling distribution of

x overbarx.

​(b) What is

Upper P left parenthesis x overbar greater than 75.9 right parenthesisP x>75.9​?

​(c) What is

Upper P left parenthesis x overbar less than or equals 68.8 right parenthesisP x≤68.8​?

​(d) What is

Upper P left parenthesis 71 less than x overbar less than 77.8 right parenthesisP 71<x<77.8​?

Use technology and the given confidence level and sample data to find the confidence interval for the population mean. Assume that the population does not exhibit a normal distribution.

Weight lost on a diet: 99% confindence n=41 dash above x = 4.0 kg s=5.9 kg

What is the confidence interval for the population mean μ ?

__kg < mean < __kg

Is the confidence interval affected by the fact that the data appear to be from a population that is not normally distributed?

A. ​No, because the population resembles a normal distribution.

B. No, because the sample size is large enough.

C. Yes, because the sample size is not large enough.

D. Yes, because the population does not exhibit a normal distribution.

Brad Pitt conducts a study comparing average numbers of people who are eaten by zombies. Do zombies prefer healthy people, people with an autoimmune disease, or people with cancer? He (carefully) observes several roving bands of zombies and collects the following data:

Complete the ANOVA Table below (please use the back of this page for your manual calculations – SHOW YOUR WORK!!), and below the ANOVA Table, write your conclusion and interpretation of the results of your ANOVA test.

ANOVA Table:

Critical F (F_c):

Conclusion & Interpretation:

In studying his campaign plans, Mr. Singleton wishes to estimate the difference between men's and women's views regarding his appeal as a candidate. He asks his campaign manager to take two random independent samples and find the 99% confidence interval for the difference. A random sample of 650 male voters and 609 female voters was taken. 363 men and 290 women favored Mr. Singleton as a candidate. Find this confidence interval.

Step 1 of 4: Find the values of the two sample proportions, pˆ1 and pˆ2. Round your answers to three decimal places.

Step 2 of 4: Find the critical value that should be used in constructing the confidence interval.

Step 3 of 4: Find the value of the standard error. Round your answer to three decimal places.

Step 4 of 4: Construct the 99% confidence interval. Round your answers to three decimal places.

Select True or False from each pull-down menu, depending on whether the corresponding statement is true or false.

  ?    True    False      1. Using the standard normal curve, the z−z−score representing the 90th percentile is 1.28.

  ?    True    False      2. The mean and standard deviation of a normally distributed random variable which has been standardized are one and zero, respectively.

  ?    True    False      3. A random variable XX is normally distributed with a mean of 150 and a variance of 36. Given that X=120X=120, its corresponding z−z− score is 5.0

  ?    True    False       Let z1z1 be a z−z− score that is unknown but identifiable by position and area. If the area to the right of z1z1 is 0.8413, the value of z1z1 is 1.0

My answer was

1. T

2. T

3.F

4. T

but I didnt get credit for that so I think there is something wrong

The following data represent the results of an independent-measures study comparing two treatment conditions.

Run the single-factor ANOVA for this data:
F-ratio:   
p-value:  

Now, run the t test on the same data:
t-statistic:   
p-value:   

1. A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 7% margin of error at a 90% confidence level, what size of sample is needed?

2. You want to obtain a sample to estimate a population proportion. Based on previous evidence, you believe the population proportion is approximately p = 0.14. You would like to be 99% confident that your estimate is within 2.5% of the true population proportion. How large of a sample size is required?

3. You want to obtain a sample to estimate a population proportion. Based on previous evidence, you believe the population proportion is approximately 74%. You would like to be 90% confident that your estimate is within 3% of the true population proportion. How large of a sample size is required?

n = ____

4. You measure 23 watermelons' weights, and find they have a mean weight of 47 ounces. Assume the population standard deviation is 12.5 ounces. Based on this, what is the maximal margin of error associated with a 95% confidence interval for the true population mean watermelon weight.

Give your answer as a decimal, to two places

±________ ounces

5. You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=71.1σ=71.1. You would like to be 95% confident that your estimate is within 10 of the true population mean. How large of a sample size is required?

n = _____

1. Brad Pitt conducts a study comparing average numbers of people who are eaten by zombies. Do zombies prefer healthy people, people with an autoimmune disease, or people with cancer? He (carefully) observes several roving bands of zombies and collects the following data:
   

Complete the ANOVA Table below (please use the back of this page for your manual calculations – SHOW YOUR WORK!!), and below the ANOVA Table, write your conclusion and interpretation of the results of your ANOVA test.

ANOVA Table:

Critical F (F_c):

Conclusion & Interpretation:

You wish to test the following claim (HaHa) at a significance level of α=0.10.

      Ho:μ1=μ2
      Ha:μ1≠μ2

You obtain the following two samples of data.

What is the test statistic for this sample? (Report answer accurate to three decimal places.)
test statistic =

What is the p-value for this sample? For this calculation, use the degrees of freedom reported from the technology you are using. (Report answer accurate to four decimal places.)
p-value =

What is the formula for a two step ahead exponential smoothing forecast?

A total of 678 women, who got pregnant under planned pregnancies, were asked how many cycles it took them to get pregnant. The women were classified as smokers and nonsmokers; it is of interest to compare the association between smoking and probability of pregnancy. The following table (Weinberg and Gladen, 1986, “The Beta-Geometric Distribution Applied to Comparative Fecundability Studies”, Biometrics 42(3): 547–560) summarises part of the data (essentially, women who had used the pill as a contraceptive are excluded).

a) Fit a geometric model, Geom(pi) to each group and compare the estimated probability of pregnancy per cycle.

b) Is there any evidence that there is an association between smoking and the probability of pregnancy? Justify your answer.

The joint PDF of X and Y is given by f(x, y) = C, (0< x<y<1).

a) Determine the value of C

b) Determine the marginal distribution of X and compute E(X) and Var(X)

c) Determine the marginal distribution of Y and compute E(Y) and Var(Y)

d) Compute the correlation coefficient between X and Y

Measuring the distance between two trees, you measure that there are 75.5 steps between the two trees. Give an estimate of the unit of measurement of one step in meters and give an estimate of what you think its uncertainty is. Give the distance that separates the trees in meters as well as feet/inches and round to the correct amount of significant digits. What would you say are the uncertainties for the these two distances

Twelve chairs are to be painted. The available colors are Red, Blue, Green, and Yellow, and every chair must be painted with one color. Assuming that all coloring schemes are equally likely, what is the probability that one color is not used and there are at least two chairs of every other color ? (The answer is 0.25) Can anyone explain to me why ?