We conduct a simple, computerized response time experiment, where participants are instructed to press the space bar as soon as a light flashes on the screen. The resulting response times are heavily right skewed, with a mean of 300 milliseconds and variance of 1000 milliseconds.

If we collect samples of 100 participants at a time, the sampling distribution of the average response time is

Group of answer choices

a.normal

b. right skewed

c. left skewed

d. bimodal

Referring to the scenario from the previous question, what is the mean of the sampling distribution? (round to nearest whole number)

Referring to the scenario from the first question, what is the variance of the sampling distribution? (round to one decimal place)

Referring to the scenario from the first question, what is the standard deviation of the sampling distribution? (round to one decimal place)

1. There are 50 parts that are checked using a GO-NOGO gauge. A GO reading would be considered a pass (or success) for the part. What is the probability that 37 parts will successfully pass?
2. Given the following table determine the mean and standard deviation

The body temperatures of adults are normally distributed with a mean of 98.6° F and a standard deviation of 0.50° F. If 25 adults are randomly selected, find the probability that their mean body temperature is greater than 98.4° F.

Confirm in testing the single restriction b1=0 that the t test is equal to the F test.

The manager of an assembly process wants to determine whether or not the number of defective articles manufactured depends on the day of the week the articles are produced. She collected the following information. Is there sufficient evidence to reject the hypothesis that the number of defective articles is independent of the day of the week on which they are produced? Use α = 0.01.

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


(ii) Find the p-value. (Round your answer to four decimal places.)


(b) State the appropriate conclusion.

Reject the null hypothesis. There is significant evidence that the number of defective articles is not independent to day of the week. Fail to reject the null hypothesis. There is not significant evidence that the number of defective articles is not independent to day of the week.     Reject the null hypothesis. There is not significant evidence that the number of defective articles is not independent to day of the week. Fail to reject the null hypothesis. There is significant evidence that the number of defective articles is not independent to day of the week.

13. Show your work for full marks: Forty-five percent of the applications received for a particular credit card are accepted. Among the next ten applications,

   A) What is the probability that all will be rejected?

2. What is the probability that all will be accepted?
3. What is the probability that exactly 4 will be accepted?
4. What is the probability that fewer than 3 will be rejected?
5. What is the probability that more than two will be rejected?(Use Excel to solve and write the function used to obtain the result.)

F) Find the expected number of accepted applications.

G) Determine the standard deviation for the number of accepted applications

A market survey was conducted in a city which numbers 16,000 homemakers. The survey was conducted to estimate the proportion of homemakers who could recognize the brand name of a cleanser based on the shape and color of the container. Of the 1,400 homemakers surveyed, 420 were able to identify the brand name. a. Using the 0.99 degree of confidence, the population proportion lies within what interval? b. An advertising firm claims that at least 30% of all homemakers can recognize the brand name of a cleanser based on the container. Do you agree? Explain.

A survey of 36 Websites selling men’s Levi jeans in the U.S. revealed that the average price of men’s Levi jeans is $47.99 with a standard deviation of $9.80. a. What is the point estimate for the population average price of men’s Levi jeans? b. What is the 98% confidence interval to estimate the true price of men’s Levi jeans? c. A clothing store wants to temporarily lower the price of men’s Levi jeans at its store to increase customer traffic. The new, lower price must be less than the average price of men’s Levi jeans in order to increase sales. The store is considering pricing the Levi jeans at $42.99, $44.81, or $47.00. Which of the three prices do you recommend? Explain.

Use a calculator to verify that x = 5807, x2 = 5,624,671, y = 579, y2 = 65,735 and xy = 553,883. Compute r. (Round your answer to three decimal places.)

Major League Baseball (MLB) consists of teams that play in the American League and the National League. MLB collects a wide variety of team and player statistics. Some of the statistics often used to evaluate pitching performance are as follows:

• ERA: The average number of earned runs given up by the pitcher per nine innings. An earned run is any run that the opponent scores off a particular pitcher except for runs scored as a result of errors.
• SO/IP: The average number of strikeouts per inning pitched.
• HR/IP: The average number of home runs per inning pitched.
• R/IP: The number of runs given up per inning pitched.

The following data show values for these statistics for a random sample of 20 pitchers from the American League for a season.

An equation given below is an estimated regression equation developed to predict the average number of runs given up per inning pitched (R/IP) given the average number of strikeouts per inning pitched (SO/IP) and the average number of home runs per inning pitched (HR/IP) (to 3 decimals). Enter negative value as negative number.

  +   +  

a. Use the  test to determine the overall significance of the relationship.

Compute  test statistic (to 2 decimals). Use F table.

The -value is - Select your answer -less than .01between .01 and .025between .025 and .05between .05 and .10greater than .10Item 5

What is your conclusion at the  level of significance?

There - Select your answer -is notisItem 6 a significant overall relationship.

b. Use the  test to determine the significance of each independent variable.

Compute the  test statistic for the significance of SO/IP (to 2 decimals). Enter negative value as negative number. Use t table.

The -value is - Select your answer -less than .01between .01 and .025between .025 and .05between .05 and .10greater than .10Item 8

What is your conclusion at the  level of significance?

SO/IP - Select your answer -is notisItem 9 significant.

Compute the  test statistic for the significance of HR/IP (to 2 decimals).

The -value is - Select your answer -less than .01between .01 and .025between .025 and .05between .05 and .10greater than .10Item 11

What is your conclusion at the  level of significance?

HR/IP - Select your answer -is notisItem 12 significant.

You are in an Intro Psych class of 137 students. You ask 25 of your classmates their age and calculate a mean of 18.2 and a sample standard deviation of 1.5. Calculate the standard error and report the 80% and 99% confidence intervals for the estimated average age of the class.

If you select 5 students from your sample where n=60, what is the probability that you will select at least 3 Females?  Create a Frequency Distribution Graph to demonstrate your outcome.

You want to compare housing prices in your community (measured in thousands of dollars) to the national values of µ= 496, σ= 36.3. Recently, 4 houses on your street were sold for a mean price of 476. Report the standard error of the mean and Z in your answers to the following questions.
Can you conclude that the mean price of housing in your community is different from the national mean at a statistically significant level?
How would your conclusion from a. change if you had obtained a sample of n= 81 with a mean of 483?
How would your conclusion from b. change if you realized that actually σ= 96.3?

Adequate Preparation for Retirement. In 2018, RAND Corporation researchers found that 71% of all individuals ages 66 to 69 are adequately prepared financially for retirement. Many financial planners have expressed concern that a smaller percentage of those in this age group who did not complete high school are adequately prepared financially for retirement.

a. Develop appropriate hypotheses such that rejection of H0 will support the con-clusion that the proportion of those who are adequately prepared financially for retirement is smaller for people in the 66–69 age group who did not complete high school than it is for the population of the 66–69 year old.
b. In a random sample of 300 people from the 66–69 age group who did not complete high school, 165 were not prepared financially for retirement. What is the p-value for your hypothesis test?
c. At a 5 .01, what is your conclusion?

1. Create a data file frame in R called musseldata which has the following observations:

species length drywght tidehght

calif     113    14.3     low

tross      48     6.9     med

calif      72     8.1     high

calif      82     8.7     med

tross      33     4.9     high

tross      51     7.0     med

calif      94   11.6     low

Type the name of the data frame and copy/paste your R command the result into the green box.

2. Use a logical condition with the subset() function to create a subset of the data called cal which contains only the observations on Mytilus californianus species (i.e. calif in the data frame). Type the name of the new data frame and the copy paste the R command you used to create the data frame, its name, and the resulting list of its contents into the green box below.

3. Use the order() function to create a listing of the data in the musseldata data frame sorted first by species, and within species, sorted by length. Copy/paste your R command and the resulting listing into the green box below.

4. Using the musseldata data frame, create a numeric vector called ratio that equals the dry weight (drywght) divided by the length. Add the ratio vector as a new variable (column) called ratio into the musseldata data frame, then type the name musseldata to display the data. Copy/paste your R commands and the resulting output into the green box below.