Questions
The ages of a random sample of people who attended a recent soccer match are as...

The ages of a random sample of people who attended a recent soccer match are as follows:

23 35 14 37 38 15 45

12 40 27 13 18 19 23

37 20 29 49 40 65 53

18 17 23 27 29 31 42

35 38 22 20 15 17 21

a. Find the mean age.

b. Find the standard deviation.

c. Find the coefficient of variation.

In: Math

An exam has 5 questions and each of them has 4 possible answers. A student gets...

An exam has 5 questions and each of them has 4 possible answers. A student gets 3 points
for each correct answer and loses 1 point for each wrong answer. Consider a student who
answers all questions completely at random. Let X denote the number of correct answers and
Y the number of points of this student at the end of the test. (A negative score is possible).
(a) Compute the mean and the standard deviation of Y , µY and σY .
(b) Compute P(µY − σY ≤ Y ≤ µY + σY ) and P(µY − 2σY ≤ Y ≤ µY + 2σY ).
(c) What is the probability that the student above gets a positive score?

In: Math

Graphically speaking, what happens to the slope of an objective function if a coefficient in the...

Graphically speaking, what happens to the slope of an objective function if a coefficient in the objective function is changed?

In: Math

5. A researcher tested a group of 11 participants with regards to their short term memory...

5. A researcher tested a group of 11 participants with regards to their short term memory on a test of a random string of digits. The collected data was as follows 7, 9, 8, 10, 8, 6, 7, 8, 7, 6, 1 (M = 7, S = 2.32). Use this sample data to,
 Make a point estimation.
 Construct an interval estimate with a 80% confidence interval.
 Construct an interval estimate with a 95% confidence interval.

In: Math

City Mileage, Highway Mileage. We expect a car's highway gas mileage to be related to its...

City Mileage, Highway Mileage. We expect a car's highway gas mileage to be related to its city gas mileage (in miles per gallon, mpg). Data for all 1137 vehicles in the government's 2013 Fuel Economy Guide give the regression line

highway mpg = 6.785 + (1.033 x city mpg)

for predicting highway mileage from city mileage.

(a) What is the slope of this line? Say in words what the numerical value of the slope tells you.

(b) What is the intercept? Explain why the value of the intercept is not statistically meaningful.

(c) Find the predicted highway mileage for a car that gets 16 miles per gallon in the city. Do the same for a car with city mileage of 28 mpg.

In: Math

Four important measurements were taken in harsh environmental conditions. Two of the four measurements were lost...

Four important measurements were taken in harsh environmental conditions. Two of the four measurements were lost in the harsh conditions and the remaining two are

5       3

However a scientist recalls the mean and variance of the four measurements were 6 and 20/3, respectively. Find the two missing measurements.

In: Math

for this problem. At least four digits after the decimal in your calculations answers May Vary...

for this problem. At least four digits after the decimal in your calculations answers May Vary slightly due to rounding a random sample of 5100 permanent dwellings on an entire reservation show that 1585 for traditional Hogan's let P be the proportion of all permanent dwellings on the entire reservation that are traditional Hogan's find a point estimate for p round your answer answer to four decimal places B find a 99% confidence interval for p round your answer to three decimal places upper and lower limits give a brief interpretation of the confidence interval see do you think the NP is greater than 5 and nq greater than 5 or satisfied for this problem explain why this would be an important consideration

In: Math

In the past, 30% of a country club's members brought guests to play golf sometime during...

In the past, 30% of a country club's members brought guests to play golf sometime during the year. Last year, the club initiated a new program designed to encourage members to bring more guests to play golf. In a sample of 80 members, 29 brought guests to play golf after the program was initiated. Therefore, the test statistic is 1.22. When testing the hypothesis that the new program has increased the proportion of members bringing out guests (using a 5% level of significance), what is the p-value? (please round your answer to 4 decimal places)

In: Math

1. Calculate the weighted unit cost per square foot for the project data shown below, and...

1. Calculate the weighted unit cost per square foot for the project data shown below, and determine the cost of a 30,000-sf project.








2. Determine the relationship between unit cost and size for the project data above, and use it to estimate the cost of a 25,000-sf project.

3. Use the time and location indices presented during Class10 to estimate the cost of a building that contains 48,000 sf of floor area. The building is to be constructed 3 years from now in City C. The cost of a similar type of building that contained 32,000 sf was completed 2 years ago in City B for a cost of $3,680,000.
Project Total Cost Size, sf 1 $ 3,036,400 26,400 2 $ 3,129,700 29,800 3 $ 2,580,300 21,500 4 $ 2,287,500 18,300 5 $ 2,743,200 23,450 6 $ 3,065,300 32,350 7 $ 4,503,600 41,700

In: Math

1. You are given with the regression result that shows the regression model with k variables....

1. You are given with the regression result that shows the regression model with k variables. Answer the following parts:

a) How do you tell that a certain variable is influential?

b) Suppose the theoretical issue said there exist a linear constraint, how do you figure out the constraint holds?

c) Suppose you have two sets of explanatory variables; how did you consider which set is the better one?

d) What’s the meaning of R-squared? Should we always look for the model that has the high R-squared?

e) Suppose the explanatory variables are subject to linear dependence among themselves, what is the correct procedure to estimate the coefficients?

In: Math

You flip a coin, if it is heads you will have a good day and if...

You flip a coin, if it is heads you will have a good day and if it is tails you will have a bad day. There are 30 days in total.

(a) What is the expectation and variance of the number of times you will have a good day throughout this 30 day stretch?

(b) What is the probability that every day will be bad for all of the 30 days?

In: Math

Calculate the value of r using the computation formula (6.1) for the following data. X Y...

Calculate the value of r using the computation formula (6.1) for the following data. X Y 2 8 4 6 5 2 3 3 1 4 7 1 2 4

quan stat

In: Math

1- critical value approach of hypothesis testing. Give an example.

1- critical value approach of hypothesis testing. Give an example.

In: Math

The accompanying data represent the pulse rates​ (beats per​ minute) of nine students. Treat the nine...

The accompanying data represent the pulse rates​ (beats per​ minute) of nine students. Treat the nine students as a population. Compute the​ z-scores for all the students. Compute the mean and standard deviation of these​ z-scores. Compute the​ z-scores for all the students. Complete the table.

Student 1 .

Student 2

Student 3

Student 4

Student 5

Student6

Student 7

Student 8

Student 9

​(Round to the nearest hundredth as​ needed.) Compute the mean of these​ z-scores.

The mean of the​ z-scores is _____

. ​(Round to the nearest tenth as​ needed.)

Compute the standard deviation of these​ z-scores. The standard deviation of the​ z-scores is ____

. ​(Round to the nearest tenth as​ needed.) Enter your answer in each of the answer boxes.

Pulse Rates Student Pulse

Student 1    77

Student 2    61

Student 3    60

Student 4    80

Student 5    73

Student 6    80

Student 7 80

Student 8    68

Student 9    73

In: Math

Should the following pairs of events be modeled as independent or dependent? Explain your reasoning. (a)...

Should the following pairs of events be modeled as independent or dependent? Explain your reasoning.

(a) We choose a voter at random (all voters equally likely) from Minneapolis. Let A be the event that the

voter favors the mayor, and B be the event that the voter favors the police chief.

(b) Two people are selected at random from Minneapolis. Let A be the event that the first person favors

the mayor, while B is the event that the 2nd person favors the mayor.

(c) Flip a coin and let A be the event that the coin is heads, and B be the event that the coin is tails.

(d) A person is selected at random from Minneapolis. Let A be the event that the person likes the movie "The

Incredibles", while B is the event that the person likes "The Incredibles 2."

In: Math