Is the magnitude of an earthquake related to the depth below the surface at which the quake occurs? Let x be the magnitude of an earthquake (on the Richter scale), and let y be the depth (in kilometers) of the quake below the surface at the epicenter. Suppose a random sample of earthquakes gave the following information.

x 2.5 4 3.4 4.4 2.4

y 5.2 10.3 10.8 10.3 8.3

Compute r.

a. 0.098

b. -0.013

c. 0.752

d. 0.013

e. -0.752

You are conducting a test of the claim that the row variable and the column variable are dependent in the following contingency table.

Give all answers rounded to 3 places after the decimal point, if necessary.

(a) Enter the expected frequencies below:

(b) What is the chi-square test-statistic for this data?
      Test Statistic: χ2=χ2=

(c) What is the critical value for this test of independence when using a significance level of αα = 0.01?
      Critical Value: χ2=χ2=  

(d) What is the correct conclusion of this hypothesis test at the 0.01 significance level?

• There is not sufficient evidence to warrant rejection of the claim that the row and column variables are dependent.
• There is not sufficient evidence to support the claim that the row and column variables are dependent.
• There is sufficient evidence to warrant rejection of the claim that the row and column variables are dependent.
• There is sufficient evidence to support the claim that the row and column variables are dependent.

Remember to give all answers rounded to 3 places after the decimal point, if necessary.

Regression Assumptions

Below are some assumptions we must meet for regression. In one or two sentences, explain what each means.

Correctly specified model?

Linearity?

Minimum multicollinearity?

Homoscedastic distribution of errors?

1.Understand how to interpret values, such as lambda, gamma, etc.

2.When is Phi appropriate?

3.When Cramer’s V appropriate?

4.What values can phi take on?

5.What if the table is larger than 2x2?

A research team conducted a study showing that approximately 15% of all businessmen who wear ties wear them so tightly that they actually reduce blood flow to the brain, diminishing cerebral functions. At a board meeting of 20 businessmen, all of whom wear ties, what are the following probabilities? (Round your answers to three decimal places.) (a) at least one tie is too tight (b) more than two ties are too tight (c) no tie is too tight (d) at least 18 ties are not too tight

a.) Given sample data: 61.2, 61.9, 62.8, 63.1, 64.0, 64.3, 64.9, 65.5, 66.3 and 67.9,
test H₀: m £ 62.89 versus H₁: m > 62.89 at a = 0.05.

b.) Test H₀: π = 0.25 versus H_A: π ¹ 0.25 with p = 0.33 and n = 100 at alpha = 0.05 and 0.10.

c.) Test at α =.05 and 0.10 the hypothesis that a majority (more than 50%) of students favor the plus/minus grading system at a university if in a random sample of 500 students, 265 favor the system?

d.) The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.0 inches and a standard deviation of 0.9 inches. A sample of 36 metal sheets is randomly selected from a batch. What is the probability that the average length of a sheet is between 29.82 and 30.27 inches long?

A research paper describes an experiment in which 74 men were assigned at random to one of four treatments.

1. viewed slides of fit, muscular men
2. viewed slides of fit, muscular men accompanied by diet and fitness-related text
3. viewed slides of fit, muscular men accompanied by text not related to diet and fitness
4. did not view any slides

The participants then went to a room to complete a questionnaire. In this room, bowls of pretzels were set out on the tables. A research assistant noted how many pretzels were consumed by each participant while completing the questionnaire. Data consistent with summary quantities given in the paper are given in the accompanying table.

Do these data provide convincing evidence that the mean number of pretzels consumed is not the same for all four treatments? Test the relevant hypotheses using a significance level of 0.05.

Calculate the test statistic. (Round your answer to two decimal places.)

F =

What can be said about the P-value for this test?

P-value > 0.1000.050 < P-value < 0.100    0.010 < P-value < 0.0500.001 < P-value < 0.010P-value < 0.001

What can you conclude?

Reject H₀. The data do not provide convincing evidence that the mean number of pretzels consumed is not the same for all four treatments.Fail to reject H₀. The data do not provide convincing evidence that the mean number of pretzels consumed is not the same for all four treatments.    Reject H₀. The data provide convincing evidence that the mean number of pretzels consumed is not the same for all four treatments.Fail to reject H₀. The data provide convincing evidence that the mean number of pretzels consumed is not the same for all four treatments.

You may need to use the appropriate table in Appendix A to answer this question.

Section 9.4 Practice Problems:

2. How many CSUN students would have to be polled to determine the percentage that hopes to transfer to UCLA to within 3.5% at

a. 95% confidence

b. 92% confidence

3. Suppose that a randomly chosen sample of 1024 airline travelers indicated that 624 checked a bag.

a. Check that this meets the conditions to find the 95% confidence interval.

b. What is the point estimate of the proportion of airline travelers that check a bag?

c. Find the 95% confidence interval for the proportion of all airline travelers that checked a bag.

i. Using the appropriate formula.

ii. Using the appropriate calculator function.

d. Interpret the interval in a sentence.

e. Can you say that a majority of airline travelers check a bag? Why or why not?

7. A health psychologist knew that corporate executives in general have an average score of 80 with a standard deviation of 12 on a stress inventory and that the scores are normally distributed. In order to learn whether corporate executives who exercise regularly have lower stress scores, the psychologist measured the stress of 55 exercising executives and found them to have a mean score of 72. Was there a significant reduction (at the .01 level)? a. What type of test would this be and why? (1pt) b. Show all steps for hypothesis testing and include a graph with your response.

when i type those python code below, i got True, but when i type not a == e or d and not c > b i still get true, why is that?  What will be the returned data type?

a = 1
b = 2
c = 3
d = True
e = 'cool'
a == e or d and c > b

Combinations question:

There are 6 employees working for a company in 6 different locations. After one year, all 6 employees must change their work location.

The new location for each employee is randomly chosen. Every location recieves exaclty one employee.

What are the possibilities for:

a) all employees recieve their old working location back.

b) no employee recieves his old working location.

c) exaclty one employee recieves his old working location.

You collected some ecological samples in a field experiment in west Texas. Collected were soil samples to determine the amount of nutrients that would need to be applied to sustain a desired level of crop growth. The observation was the amount of nutrient the soil contained. Samples were taken from 100 different locations. It was found that the nutrient data are normally distributed. The mean value of the samples was 16 units (the exact name for the units do not really matter in this problem, so just call them “units”). The sample standard deviation of the samples is 3.5 units.

a. estimate the probability range for the Confidence Interval of the Mean (95% confidence) for the parameters given above.

b. What is the interpretation of the Confidence Interval of the Mean?

c. Consider the experiment was performed again in a second year, however, this time only 15 sites were sampled. The mean value in year two was found to be 14.5 units and the sample standard deviation was found to be 2.2 units. Using equation 3.16, estimate the probability ranges for the 90%, 95%, and 99% confidence intervals of the mean.. You will need to estimate THREE probability ranges to answer this question. One range for 90%; one range for 95%, and one range for 99%.

d. Describe how the probability range changes as the confidence interval increases. e. What is the probability range for the 50% confidence?

f. If you were to repeat the experiment described initially (100 samples per year) for twenty years, what percentage of the years would you expect the true mean value to be bracketed by the 50% confidence interval? Additionally, what percentage of the years would you expect the true mean value to be bracketed by the 95% confidence interval

Edit: Please show work on how to calculate Confidence intervals.

In the National AIDS Behavioral Surveys sample of 2723 adult heterosexuals, 8 respondents had both received a blood transfusion and had a sexual partner from a group at high risk of AIDS. You should not use the large-sample confidence interval for the proportion p in the population who share these two risk factors. The plus four method adds four observations, two successes and two failures.

What is the plus four estimate pˆp^ (±0.0001) of p? p~ = ……...

Give the plus four 93% confidence interval (±0.0001) for p:...… ⩽ p ⩽ ……….

the percentage of deaths due to disease is 12.5%. A medical student wants to test whether the percentage of deaths due to disease is less than 12.5%. She collected data on deaths due to disease over 8 states. She found out that there were 102 patients diagnosed with disease and 11 patients died. Carry out a test of significance by answering the questions below in as much detail as possible. Use a 10% level of significance. What is the value of the test statistic? (Hint: Round sample proportion to four decimal places.) Question 2 options: A) -0.53 B) 0.53 C) 0.01 D) -0.01 E) -0.05