A company announced a "1000 Chips Trial" claiming that every 18 ounce bag of its cookies contained at least 1000 chocolate chips. Students purchased random bags from cookies from different stores and counted the number of chips in each bag. Some of the data is shown below.

1042 1132 1134 1255 1278 1233 1265 1339 1311 1450

Q1--Create a 95% confidence interval for the average number of chips. (SHOW EVERY STEP, I am completely lost on how to do this).

Q2--What percentage of bags will have fewwer then 1000 chips. (SHOW EVERY STEP).

**Only answer G-J, I already did A-F**

2. Measuring the height of a California redwood tree is very difficult because these trees grow to heights over 300 feet. People familiar with these threes understand that the height of a California redwood tree is related to other characteristics of the tree, including the diameter of the tree at the breast height of a person (in inches), the thickness of the bark of the tree (in inches), the distance from the closest neighboring tree (in yards), and the number of the other trees neighboring within 10 yards from the tree. Using the data set (Redwood.xlsx), conduct a regression analysis by answering the following questions.

(g) Determine the coefficient of determination, ? 2 , and interpret its meaning (f) At the level ? = 0.10, is there a significant relationship between the thickness and the pressure? Answer based on the t test in the p-value approach

(h) Determine the adjusted coefficient of determination, adjusted ? 2 , and interpret its meaning

(i) Evaluate the linearity assumption using the residual plot about the independent variable for diameter

(j) Evaluate the normality assumption using the normal probability plot

home / study / business / finance / finance questions and answers / a researcher collected data from a random sample of 25 high school freshmen and found the mean ...

Question: A researcher collected data from a random sample of 25 high school freshmen and found the mean of...

A researcher collected data from a random sample of 25 high school freshmen and found the mean of the sample to be 85.40 on the Test of Critical Thinking (TCT). She also calculated the standard deviation from the sample and discovered the value was 12.30. The average score on the Test of Critical Thinking for all high school seniors in a large school district is 90.00. The researcher wants to know if the mean TCT of the 25 high school freshmen in the random sample is different from the population’s (i.e., high school seniors) TCT mean.

e.What decision should be made about the null hypothesis? In other words, should you reject or retain the null hypothesis?
f. Construct a 95% confidence interval around the sample mean of 85.40. Does this confidence interval contain the population mean of 90.00?
g. Provide a brief conclusion regarding your findings. Use your powerpoint lecture slides for writing out the interpretation of your results.
[ME: What decision should be made about the null hypothesis? In other words, should you reject or retain the null hypothesis? (10p) e. f. Construct a 95% confidence interval around the sample mean of gaps. Does this confidence interval contain the population mean of 90.00? (Extra credit:10p) Provide a brief conclusion regarding your findings. Use your powerpoint lecture slides for writing out the interpretation of your results. (10p) g.]

9. The table below gives the number of hours five randomly selected students spent studying and their corresponding midterm exam grades. Using this data, consider the equation of the regression line, yˆ=b0+b1x, for predicting the midterm exam grade that a student will earn based on the number of hours spent studying. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant.

Hours Studying   1 2 3 4 5

Midterm Grades 62 66 76 77 81

Step 1 of 6: Find the estimated slope. Round your answer to three decimal places.

Step 2 of 6: Find the estimated y-intercept. Round your answer to three decimal places.

Step 3 of 6: Find the estimated value of y when x=2. Round your answer to three decimal places.

Step 4 of 6: Determine the value of the dependent variable yˆ at x=0.

Step 5 of 6: Find the error prediction when x=2. Round your answer to three decimal places.

Step 6 of 6: Find the value of the coefficient of determination. Round your answer to three decimal places.

The _______ is usually the hypothesis that the researcher wants to gather evidence against.

                null hypothesis

                alternative hypothesis

                one-tailed hypothesis

                two-tailed test of hypothesis

The _______ is usually the hypothesis for which the researcher wants to gather supporting evidence.

                one-tailed test of hypothesis

                null hypothesis

                two-tailed test of hypothesis

                alternative hypothesis

1. In a study of red/green color blindness, 700 men and 2050 women are randomly selected and tested. Among the men, 62 have red/green color blindness. Among the women, 4 have red/green color blindness. Test the claim that men have a higher rate of red/green color blindness.
The test statistic is  
The p-value is  
Is there sufficient evidence to support the claim that men have a higher rate of red/green color blindness than women using the 0.01% significance level?

A. No
B. Yes

2. Construct the 99% confidence interval for the difference between the color blindness rates of men and women.
<(p1−p2)<  

Which of the following is the correct interpretation for your answer in part 2?
A. We can be 99% confident that the difference between the rates of red/green color blindness for men and women lies in the interval
B. There is a 99% chance that that the difference between the rates of red/green color blindness for men and women lies in the interval
C. We can be 99% confident that that the difference between the rates of red/green color blindness for men and women in the sample lies in the interval
D. None of the above

1. In testing the null hypothesis that p = 0.3 against the alternative that p not equal 0.3, the probability of a Type II error is _____________ when p = 0.4 than when p = 0.6.

a. the same

b. smaller

c. larger

d. none of the above

2. During the pre-flight check, Pilot Jones discovers a minor problem - a warning light indicates that the fuel guage may be broken. If Jones decides to check the fuel level by hand, it will delay the flight by 45 minutes. If Jones decides to ignore the warning, the aircraft may run out of fuel before it gets to Gimli. In this situation, what would be:

i) the appropriate null hypothesis? and;
ii) a type I error?

Question 2 options:

What are the focuses of these two fields of psychology? How has both fields of study evolved over the last 10 years. 1000 word essay

Chapter 9, Section 3, Exercise 057

Two intervals are given, A and B, for the same value of the explanatory variable. A: 3.9 to 6.1; B: 2.6 to 7.4

(a) Which interval is the confidence interval for the mean response? A or B? Which interval is the prediction interval for the response? A or B?

(b) What is the predicted value of the response variable for this value of the explanatory variable?

Enter the exact answer.

The predicted value is

8. Consider the relationship between the number of bids an item on eBay received and the item's selling price. The following is a sample of 5 items sold through an auction.

Price in Dollars 20 36 38 41 42

Number of Bids 5 5 5 8 8

Step 1 of 5: Calculate the sum of squared errors (SSE). Use the values b0= 2.1396 and b1= 0.1147 for the calculations. Round your answer to three decimal places.

Step 2 of 5: Calculate the estimated variance of errors, s2e. Round your answer to three decimal places.

Step 3 of 5: Calculate the estimated variance of slope, s2b1. Round your answer to three decimal places.

Step 4 of 5: Construct the 95% confidence interval for the slope. Round your answers to three decimal places.

Lower endpoint and Upper endpoint

Step 5 of 5: Construct the 90% confidence interval for the slope. Round your answers to three decimal places.

Lower endpoint and Upper endpoint

Use Minitab to answer the questions. Make sure to copy all output from the Minitab:

The U.S. Bureau of Labor Statistics publishes a variety of unemployment statistics, including the number of individuals who are unemployed and the mean length of time the individuals have been unemployed. For November 1998, the Bureau of Labor Statistics reported that the national mean length of time of unemployment was 14.5 weeks.

The mayor of Chicago has requested the study on the status of unemployment in City of Chicago. A sample of 60 unemployed residents shows the sample mean is 15.7 and the sample standard deviation is 9.0. Test whether the length of time in Chicago is long than national average.

1) Let's think about the house price. According to the Case-Shiller Home Price Indices in August 2009, Chicago and San Francisco have following sample mean and population standard deviations (the sample mean was calculated by daily base, so the sample size was 30):

Using hypothesis test, prove if these house price indices are same.  (Setup a hypothesis, show your works to perform the test, and state your verdict)

2)             Some people argue that San Francisco has higher house price than that of Chicago. Prove/disprove the argument using a hypothesis test.

3)             Let’s assume the population standard deviations are unknown, and the sample standard deviation of for Chicago is 9.2 and that of San Francisco is 11.5. Some people argue that San Francisco has higher variability (higher variance) in house prices than that of Chicago. Setup a hypothesis, perform the test and prove/disprove the argument.

4.     Let’s consider a company’s growth rate of sales.

Find the sample mean and sample standard deviation using Minitab using descriptive statistics.

The store manager found that the average growth rate in 80s was 6.00%. Using the data, prove if the average growth rate for the sample period was same as that of 80s.

Prove if the average growth rate was less than 6%.

In a study of high school students at least 16 years of age, researchers obtained survey results summarized in the accompanying table (based on data from Texting While Driving and Other Risky Motor Vehicle Behaviors Among U.S. High School Students, by OMalley, Shults, and Eaton, Pediatrics, Vol. 131, No. 6).

Use a 0.05 significance level to test, by hand, the claim of independence between texting while driving and irregular seat belt use:

1. (a) State the null and alternative hypotheses, indicate the significance level and the type of test (left-, right-, or two-tailed test).

2. (b) Calculate by hand the test statistic

3. (c) Use the χ2 table to identify the critical value

4. (d) Use the test statistic and critical value to explain whether or not the null hypothesis is rejected.

5. (e) Make a concluding statement.

6. (f) Are those two risky behaviors independent of each other?

MANAGING ASHLAND MULTI-COMM SERVICES

The AMS technical services department has embarked on a quality improvement effort. It’s first project relates to maintaining the target upload speed for its Internet service subscribers. Upload speeds are measured on a standard scale in which the target value is 1.0. Data collected over the past year indicate that the upload speed is approximately normally distributed, with a mean of 1.005 and a standard deviation of 0.10. Each day, one upload speed is measured. The upload speed is considered acceptable if the measurement on the standard scale is between 0.95 and 1.05

1. Assuming that the distribution has not changed from what it was in the past year, what is the probability that the upload speed at any time is:

a. Less than 1.0?

b. Between 0.95 and 1.0?

c. Between 1.0 and 1.05?

d. Less than 0.95 or greater than 1.05?

2. The objective of the operations team is to reduce the probability that the upload speed is below 1.0. Should the team focus on process improvement that increases the mean upload speed to 1.05, or on process improvement that reduces the standard deviation of the upload speed to 0.75? Explain.

For questions 2-7: state the appropriate hypotheses; conduct a hypothesis test using α = 0.05 utilizing the classical approach, confidence interval approach, or p-value approach; state the decision regarding the hypotheses; and make a conclusion.

3. (15 pts) In a study of schizophrenia, researchers measured the activity of the enzyme monoamine oxidase (MAO) in the blood platelets of 18 patients. The results (expressed as nmol benzylaldehyde product per 108 platelets) were as follows:

6.8 8.4 8.7 11.9 14.2 18.8

9.9 4.1 9.7 12.7 5.2 7.8 7.8

7.4 7.3 10.6 14.5 10.7

The researchers believe that the average MAO level should be 7.5 amongst the general population, which is assumed to follow a normal distribution. Elevated MAO levels are considered abnormal.

7. (15 pts) The manager of a fast-food restaurant claims that the average service time is less than 90 seconds. A random sample of customers is selected and their wait times are reported as follows:

56 78 66 78 99 114 106 92 45 102

119 84 88 118 99 61 55 79 108 46

75 102 70 74 72 113 83 78 105 81

Explain Central Limit Theorem.     

What is the sampling distribution of the mean?

Explain the differences between a discrete random variable and a continuous random variable.