Questions
Assuming a normal distribution with a mean of 5 and standard deviation of 1.2, what is...

  1. Assuming a normal distribution with a mean of 5 and standard deviation of 1.2, what is the P(X = 6)?
    1. 0
    2. 0.2033
    3. -0.8333
    4. 0.8333

  2.   Assuming the expected value of a distribution is 4 and the standard deviation is 0.85, what would be the expected value if a constant of 1 added to each value of x?
    1. 4.00
    2. 4.85
    3. 5.00
    4. 5.85

  3. What distribution would you use if you want to find the expected number of heads when you flip a coin 100 times?
    1. Normal
    2. Uniform
    3. Geometric
    4. Binomial

  4.   What distribution would you use if you want to find the expected number of times you have to roll a die until you get a 6?
    1. Normal
    2. Uniform
    3. Geometric
    4. Binomial
  5.   What is the expected number of times you will get heads if you flip a fair coin (50/50 chance of heads or tails), if you flip the coin 5,000 times?
    1. 0
    2. 50
    3. 2500
    4. 5000

In: Math

A study of the career paths of hotel general managers sent questionnaires to an SRS of...

A study of the career paths of hotel general managers sent questionnaires to an SRS of 250 hotels belonging to major U.S. hotel chains. There were 127 responses. The average time these 127 general managers had spent with their current company was 8.92 years. (Take it as known that the standard deviation of time with the company for all general managers is 2.8 years.)

(a) Find the margin of error for a 90% confidence interval to estimate the mean time a general manager had spent with their current company: years

(b) Find the margin of error for a 99% confidence interval to estimate the mean time a general manager had spent with their current company: years

(c) In general, increasing the confidence level the margin of error (width) of the confidence interval. (Enter: ''DECREASES'', ''DOES NOT CHANGE'' or ''INCREASES'', without the quotes.)

In: Math

Consider your dissertation research interests. Identify one categorical/nominal scale IV with more than 2 categories, and...

Consider your dissertation research interests. Identify one categorical/nominal scale IV with more than 2 categories, and three DVs that are measured on continuous scales. Think of DV measures that probably are moderately correlated with each other because they are measuring different components of the same or similar concepts (e.g., three different measures of academic performance). What information would a one-way MANOVA provide you? What more would you want to know if you get significant results in the MANOVA? Why would this be significant to your research? Please type about a 200 word response and use IQ as as the topic. Thanks

In: Math

I am working on a method section for a paper. The experiment in general terms is...

I am working on a method section for a paper. The experiment in general terms is testing to see if there is a significance between two treatment groups in substance abuse recovery. One group is an exercise group the other is not. the sample population is about 100 individuals and 50 in each category. All individuals will be asked yes or no if they relapsed over the last year. What would be the best statistical analysis test for determining if this is chance or if there is significance.

In: Math

A class survey in a large class for first-year college students asked, "About how many minutes...

A class survey in a large class for first-year college students asked, "About how many minutes do you study on a typical weeknight?" The mean response of the 257 students was x¯¯¯x¯ = 140 minutes. Suppose that we know that the study time follows a Normal distribution with standard deviation σσ = 65 minutes in the population of all first-year students at this university.

Use the survey result to give a 95% confidence interval for the mean study time of all first-year students.

please explain your process. Thank you

In: Math

According to the British United Provident Association, a major health care provider in the U.K., snoring...

According to the British United Provident Association, a major health care provider in the U.K., snoring can be an indication of sleep apnea which can cause chronic illness if left untreated. In the United States, the National Sleep foundation reports that 36.8% of the 995 adults they surveyed snored. Of the respondents, 81.5% were over the age of 30, and 32% were both over the age of 30 and snorers.

a. Are the two events of being older than 30 and “did not snore, mutually exclusive? (prove mathematically)

b. Is snoring independent of age? Explain and prove mathematically.

In: Math

There are three hospitals in the Tulsa, Oklahoma, area. The following data show the number of...

There are three hospitals in the Tulsa, Oklahoma, area. The following data show the number of outpatient surgeries performed on Monday, Tuesday, Wednesday, Thursday, and Friday at each hospital last week. At the 0.01 significance level, can we conclude there is a difference in the mean number of surgeries performed by hospital or by day of the week?

Number of Surgeries Performed
Day St. Luke's St. Vincent Mercy
Monday 30 45 34
Tuesday 12 16 12
Wednesday 31 28 23
Thursday 11 14 13
Friday 20 32 25


1. Set up the null hypothesis and the alternate hypothesis.

2. State the decision rule for 0.01 significance level. (Round your answers to 2 decimal places.)

For Treatment: Reject H0 if F > ________

For blocks: Reject H0 if F > ________

3. Complete the ANOVA table. (Round your SS, MS and F to 2 decimal places.)

Source SS df MS F
Treatments
Blocks
Error
Total

In: Math

A sample of 1600 computer chips revealed that 47% of the chips fail in the first...

A sample of 1600 computer chips revealed that 47% of the chips fail in the first 1000 hours of their use. The company's promotional literature states that 44% of the chips fail in the first 1000 hours of their use. The quality control manager wants to test the claim that the actual percentage that fail is different from the stated percentage. Is there enough evidence at the 0.01 level to support the manager's claim?

In: Math

7) Personal phone calls received in the last three days by a new employee were 4,...

7) Personal phone calls received in the last three days by a new employee were 4, 1, and 8. Assume that samples of size 2 are randomly selected with replacement from this population of three values. a) List the nine different possible samples of size 2 and find the mean of each of them. b) The probability for each sample mean in Part a) is 1/9. Summarize your results in Part a) by construct ing a sampling distribution for these sample means. c) Find the expected value based on Part b). This expected value is also the mean of all the nine sample means found in Part a). d) Find the population mean of the personal phone calls received in the last three days by a new employee: {2, 3, 7} and compare it with your result in Part c).

In: Math

The distribution of birthweight of singletons in city of Tianjin, China is approximately normal with mean...

The distribution of birthweight of singletons in city of Tianjin, China is approximately normal with mean m=3,445 grams and standard deviation = 409 grams [2]. An investigator plans to conduct a study to determine if birthweight for singletons whose mothers were with gestational diabetes mellitus (GDM) have the same mean. Based on literature search, the true mean birthweight for infants whose mothers with GDM is estimated 3,800 grams (± 250 grams). The investigator wants 90% power to detect the differences. A two-tails test conducted at the 0.05 level of significance will be used. What sample size is needed for this study? if the power is changed to 80%, what sample size is then needed?

In: Math

In a random sample of 39 criminals convicted of a certain​ crime, it was determined that...

In a random sample of 39 criminals convicted of a certain​ crime, it was determined that the mean length of sentencing was 57 ​months, with a standard deviation of 7 months. Construct a 95​% confidence interval for the mean length of sentencing for this crime.

the 95​% confidence interval is ​(?,?)

In: Math

A bakery would like you to recommend how many loaves of its famous marble rye bread...

A bakery would like you to recommend how many loaves of its famous marble rye bread to bake at the beginning of the day. Each loaf costs the bakery $2.00 and can be sold for $7.00. Leftover loaves at the end of each day are donated to charity. Research has shown that the probabilities for demands of 25, 50, and 75 loaves are 35%, 20%, and 45%, respectively. Make a recommendation for the bakery to bake 25, 50, or 75 loaves each morning.

Find the expected monetary value when baking 25 loaves.

Find the expected monetary value when baking 50 loaves.

Find the expected monetary value when baking 75 loaves.

In: Math

In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of...

In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of freedom d.f. not in the Student's t table, use the closest d.f. that is smaller. In some situations, this choice of d.f. may increase the P-value by a small amount and therefore produce a slightly more "conservative" answer. At five weather stations on Trail Ridge Road in Rocky Mountain National Park, the peak wind gusts (in miles per hour) for January and April are recorded below. Weather Station 1 2 3 4 5 January 139 124 128 64 78 April 108 115 100 88 61 Does this information indicate that the peak wind gusts are higher in January than in April? Use α = 0.01. (Let d = January − April.) (a) What is the level of significance? State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test? H0: μd = 0; H1: μd ≠ 0; two-tailed H0: μd = 0; H1: μd < 0; left-tailed H0: μd > 0; H1: μd = 0; right-tailed H0: μd = 0; H1: μd > 0; right-tailed (b) What sampling distribution will you use? What assumptions are you making? The Student's t. We assume that d has an approximately uniform distribution. The Student's t. We assume that d has an approximately normal distribution. The standard normal. We assume that d has an approximately uniform distribution. The standard normal. We assume that d has an approximately normal distribution. What is the value of the sample test statistic? (Round your answer to three decimal places.) (c) Find (or estimate) the P-value. P-value > 0.250 0.125 < P-value < 0.250 0.050 < P-value < 0.125 0.025 < P-value < 0.050 0.005 < P-value < 0.025 P-value < 0.005 Sketch the sampling distribution and show the area corresponding to the P-value. WebAssign Plot WebAssign Plot WebAssign Plot WebAssign Plot (d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis? Are the data statistically significant at level α? At the α = 0.01 level, we fail to reject the null hypothesis and conclude the data are statistically significant. At the α = 0.01 level, we reject the null hypothesis and conclude the data are not statistically significant. At the α = 0.01 level, we fail to reject the null hypothesis and conclude the data are not statistically significant. At the α = 0.01 level, we reject the null hypothesis and conclude the data are statistically significant. (e) State your conclusion in the context of the application. Reject the null hypothesis, there is insufficient evidence to claim average peak wind gusts are higher in January. Fail to reject the null hypothesis, there is insufficient evidence to claim average peak wind gusts are higher in January. Reject the null hypothesis, there is sufficient evidence to claim average peak wind gusts are higher in January. Fail to reject the null hypothesis, there is sufficient evidence to claim average peak wind gusts are higher in January.

In: Math

Determine the sample size n needed to construct a 99​% confidence interval to estimate the population...

Determine the sample size n needed to construct a 99​% confidence interval to estimate the population proportion when p overbar =0.68 and the margin of error equals 5​%.

n=_______ ​(Round up to the nearest​ integer.)

____________________________________________________________________________________________________________________________

Determine the sample size n needed to construct a 99​% confidence interval to estimate the population mean for the following margins of error when σ=87. ​a) 25 ​b) 40 ​c) 50

In: Math

“Countries that have single member district elections will have fewer political parties than countries that have...

“Countries that have single member district elections will have fewer political parties than

countries that have proportional representation elections.”

a. In this hypothesis, state the independent variable, and give examples of two values

that it can take on.

b. State the dependent variable, and give two values that it can take on.

c. Propose one intervening variable that could complete the causal path between the

independent variable and the dependent variable. Explain how it might play this role.

d. Harder. Can you think of a possible confounding variable that might explain the

relationship? Explain how it might play this role.

In: Math