1. During routine conversations, the CEO of a new start up reports that 15% of adults between the ages of 21 and 39 will purchase her new product. Hearing this, some investors decide to conduct a large scale study, hoping to estimate the proportion to within 5% with 90% confidence. How many randomly selected adults between the ages of 21 and 39 must they survey?

 

 

The number of adults that should be surveyed is 138 (Round up to the nearest whole number).

 

 

1. A random sample of 20 purchases showed the amounts in the table (in $). The mean is $52.08 and the standard deviation is $20.92.

a)      What is the standard error of the mean?

b)      How would the standard error change if the sample size had been 5 instead of 20? (Assume that the sample standard deviation didn’t change).

 

Table:

 

80.70             45.42     46.89     83.80

28.19             48.65     29.17     50.75

31.17             72.20     32.29     52.41

72.43             33.13     74.04     87.73

16.41             38.40     58.79     59.00

 

 

a)      The standard error of the mean is 4.68(Round to two decimal places as needed)

b)      How would the standard error change if the sample size was 5 instead of 20 with the same sample standard deviation? Select the correct choice below and fill in any answer boxes within your choice.

 

a)      The standard error would increase. The new standard error would be 2 times the old.

 

b)      The standard error would decrease. The new standard error would be the old standard error divided by _____________

 

c)      The standard error would not change.

 

1. Top management at a large Software company wishes to estimate the average number of hours its firm’s professional employees volunteer in the local community. Based on past similar studies, the standard deviation was found to be 2.22 hours. If top management wants to estimate the average number of hours volunteered per month by their professional staff to within one hour with 99% confidence, how many randomly selected professional employees would they need to sample?

 

a)      19

b)      44

c)       33

d)      25

e)      54

 

 

1. A young investor believes that he can beat the market by pricing stocks that will increase in value. Assume that on average 52% of the stocks selected by a portfolio manager will increase over 12 months. Of the 29 stocks that the young investor bought over the last 12 months, 17 have increased. Can he claim that he is better at predicting increases that the typical portfolio manager? Test at a = 0.05

 

What is the null and alternative hypothesis for this test?

 

a)     

b)     

c)      

d)     

 

Calculate the test statistic.

 

Z = 0.714(Round to three decimal places as needed)

What is the P-value for the test statistic?

 

P-Value =0.238(Round to three decimal places).

 

What can the investor conclude? Assume  a=0.05

 

a)      He rejects the null hypothesis and cannot claim that he is better at predicting increases than the typical portfolio manager.

b)      He fails to reject the null hypothesis and can claim that he is better at predicting increases than the typical portfolio manager, but this conclusion may not be reliable. ‘

c)       He fails to reject the null hypothesis and can not claim that he is better at predicting increases than the typical portfolio manager, but this conclusion may not be reliable.

d)      He rejects the null hypothesis and can claim that he is better at predicting increases than the typical portfolio manager, but this conclusion may not be reliable.

 

 

 

1. A random sample of the amounts for 16 purchases was taken. The mean was $44.37, the standard deviation was $23.32, and the margin of error for a 95% confidence interval was $12.43.

 

a)      To reduce the margin of error to about $6, how large would the sample size have to be?

b)      How large would the sample size have to be to reduce the margin of error to $1.2?

 

 

a)      The new sample size should be69(Round up to the nearest integer)

b)      The new sample size should be 1717(Round up to the nearest integer).

 

 

 

 

Figure 7-5.On the graph below, Q represents the quantity of the good and P represents the good’s price.

 

 

 

 

Refer to Figure 7-5. If the price of the good is $14, then producer surplus is

a.	$17.
b.	$22.
c.	$25.
d.	$28.

 

 

Figure 7-9

 

 

Refer to Figure 7-9. If the price decreases from $22 to $16, consumer surplus increases by

a.	$120.
b.	$360.
c.	$480.
d.	$600.

 

Refer to Figure 7-9. IF 40 units of the good are being bought and sold, then

1. The marginal cost to seller is equal to the marginal value to buyers
2. The marginal value to buyers is greater than the marginal cost to seller
3. The marginal cost to sellers is greater than the marginal value to buyers
4. Producer surplus would be greater than consumer surplus.

 

 

 

 

Figure 7-20

 

 

	K    Supply

 

 

 

 

Price

48

44     A

40

36

32     F                                                              G

 

Demand

28

24     H

20                                                                                                           B                                                                            

16

12

8        C

4

 

             1         2        3        4       5     6        7        8        9        10        11    Quantity

 

 

 

Refer to Figure 7-20. At Equilibrium, total surplus is

1. $36
2. $72
3. $108
4. $144

Figure 8-2          

The vertical distance between points A and B represents a tax in the market.

 

Refer to Figure 8-2  

The loss of consumer surplus as a result of the tax is

1. $1.50    B.    $3   C.    $4.50   D.   $6.

 

 I NEED A POSITIVE COMMENT BASED IN THIS ARGUMENT. BETWEEN 150-200 WORDS

 

Mean, median and mode are all valid measures of central  tendency, but under different situations, some measures of tendency  become more appropriate to use than others. The different situations  are when the populations are not uniform, that is when you use them  separately according to the one that is suitable for that particular  instance (Park, 2015).
 

 One can use mean/ median or mode in  a population that is uniform. A normal population will consist of same  people with the same goal to achieve. An example of such population is  students. In class, the measures of central tendency will be used to  grade students after the results and get their mean. Another  characteristic of a population that we can use the measures of central  tendency is where the population is non-uniform regarding age, height,  weight, etc. In such a situation, if we need to get a value that will  be applied to that population, we need to get a normal number that  will take care of the smallest and the biggest. The measure of central  tendency will be mean. The mean will be the average of the total  number of that population (Cuevas, 2014).

 The other characteristic of a population that you can use  measures of central tendency will be the gender. Regarding a gender,  you may find that a certain gender is dominant. The number of males  may be higher than that of females. In this case, the mode is used to  know the type of gender that is high in number. Mode gives the highest  number of an element that is repeated most (Park, 2015).

 

Reference

Cuevas, A. (2014). A partial overview of the theory of statistics  with functional data. Journal of Statistical Planning and Inference,  147, 1-23.

Park, H. M. (2015). Univariate analysis and normality test using  SAS, Stata, and SPSS.

 

 

 

A growing trend in the entertainment/music industry that will have an impact on me within the next two years is the expansion of digital music.  According to Mathias Brandt (2013), “In 2017 179 million people in the U.S. will tune in to a digital radio station at least once a month, 108 million are to use their mobile phone to listen to music…”, which will change the dynamics on how people are listening to music.  Consumers are embracing the digital age of music and folks are no longer tuning in via traditional radio stations, but rather taking their music on the go.  Whether it be on a smartphone, iPod/iPad, or a mp3 player, music has evolved.  I would improve this chart to reflect not just the US, but also other areas such as the European and Asian markets to get a clear view on how the digital age of music is being in embraced by all music listeners. The three external factors that could change this trend are 1) will traditional radio station owners complain if digital radio stations are under the same rules and procedures as they are, 2) are music sales being effective by possible piracy with the use of digital radio, and 3) has the music industry accepted the use of digital music and how it is being distributed either through the black markets or via pirate methods.

 

HERE IS THE LINK TO THE GRAPH: https://fso-lms4-mortal-assets.s3.amazonaws.com/%2F106544/20175/Digital%20Music%20Trend.jpg?versionId=zz438ucX8DJLQIK_3Cd3Q3BHQGy0vsag&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20170515T192258Z&X-Amz-SignedHeaders=host&X-Amz-Expires=600&X-Amz-Credential=AKIAI4QJ7YJDQ7JYMBXQ%2F20170515%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=248d5acf3a2270419904563708b5760c3f990c24205caf0cc60bae2c0f91eeab

 

I ONLY NEED A RESPONSE TO THIS POST AND GRAPH…….

 

1. Select a classmate’s linked chart and provide an appropriate message the selected chart is attempting to convey.
2. Do you feel the original author of the chart accomplished this message?
3. In one paragraph, describe how the trend your classmate selected would have an impact on your personally or professionally.
4. Expand on the external factors listed.  Do you agree with these influences?
5. Apply the RISE model

 

I promise this will help you ace your statistics midterm exam. If you need further help, just message me in this website. I am archmage, a statistics expert tutor. Godbless!

 

1.The MPG (miles per gallon) for a certain compact car is normally distributed with a mean of 31 and a standard deviation of 0.8. What is the probability that the MPG for a randomly selected compact car would be less than 32?

                0.5596

                0.3944

                0.8944

                0.1056

2.In a simple regression, there are n – 2 degrees of freedom associated with the error sum of squares (SSE).

                True

                False

3.A researcher’s results are shown below using Femlab (labor force participation rate among females) to try to predict Cancer (death rate per 100,000 population due to cancer) in the 50 U.S. states.

 

 Source of variation         df            SS           MS         F

Regression          1              5377.836              5377.836              5.228879

Residual               48           49367.389            1028.487             

Total      49           54745.225                           

 

 

What is the R2 for this regression?

                .1605

                .0982

                .9018

                .8395

 [The following information applies to the questions displayed below.]

 

 

The sodium content of a popular sports drink is listed as 204 mg in a 32-oz bottle. Analysis of 14 bottles indicates a sample mean of 210.5 mg with a sample standard deviation of 24.2 mg.

 

 

 4.(a)     

State the hypotheses for a two-tailed test of the claimed sodium content.

                H0: µ ≤ 204 vs. H1: µ > 204

                H0: µ = 204 vs. H1: µ ≠ 204

                H0: µ ≥ 204 vs. H1: µ < 204

 

 5.

(b)         

Calculate the t test statistic to test the manufacturer’s claim. (Round your answer to 4 decimal places.)

 

  Test statistic      

 

 

 6.

(c)

At the 1 percent level of significance (α = 0.01) does the sample contradict the manufacturer’s claim?

                 

                  

H0. The sample

the manufacturer’s claim.

 

 

 7.

(d-1)     

 

Use Excel to find the p-value and compare it to the level of significance. (Round your answer to 4 decimal places.)

                 

                  The p-value is . It is

than the significance level 0.01.

                 

(d-2)      Did you come to the same conclusion as you did in part (c)?

                 

               

                Yes

                No

8.A charity raffle prize is $1,000. The charity sells 4,000 raffle tickets. One winner will be selected at random. At what ticket price would a ticket buyer expect to break even?

                $0.25

                $0.50

                $0.75

                $1.00

9.At Joe’s Restaurant, 80 percent of the diners are new customers (N), while 20 percent are returning customers (R). Fifty percent of the new customers pay by credit card, compared with 70 percent of the regular customers. If a customer pays by credit card, what is the probability that the customer is a new customer?

                .7407

                .5000

                .5400

                .8000

10.Within a given population, 22 percent of the people are smokers, 57 percent of the people are males, and 12 percent are males who smoke. If a person is chosen at random from the population, what is the probability that the selected person is either a male or a smoker?

                .67

                .22

                .43

                .79

11.A fair die is rolled. If it comes up 1 or 2 you win $2. If it comes up 3, 4, 5, or 6 you lose $1. Find the expected winnings.

                $1.00

                $0.50

                $0.00

                $0.25

12.Assume that X is normally distributed with a mean μ = $64. Given that P(X ≥ $75) = 0.2981, we can calculate that the standard deviation of X is approximately:

                $13.17.

                $5.83.

                $7.05.

                $20.76.

13.If the attendance at a baseball game is to be predicted by the equation Attendance = 16,500 – 75 Temperature, what would be the predicted attendance if Temperature is 90 degrees?

                9,750

                6,750

                10, 020

                12,250

 [The following information applies to the questions displayed below.]

 

A random sample of 140 items is drawn from a population whose standard deviation is known to be σ = 50. The sample mean is x = 780.

 

 

 14.

(a)         

Construct an interval estimate for μ with 98 percent confidence. (Round your answers to 4 decimal places.)

 

 

 

  The 98 percent confidence interval is from         to . 

 

 

 

 15.

(b)         

 

Construct an interval estimate for μ with 98 percent confidence, assuming that σ = 100. (Round your answers to 4 decimal places.)

 

  The 98 percent confidence interval is from         to .

 

 

 16.

(c)          

 

Construct an interval estimate for μ with 98 percent confidence, assuming that σ = 200. (Round your answers to 4 decimal places.)

 

  The 98 percent confidence interval is from         to .

 

 

 17.

(d)          Describe how the confidence interval changes as σ increases.

                The interval stays the same as σ increases.

                The interval gets wider as σ increases.

                The interval gets narrower as σ increases.

                The interval gets wider as σ decreases.

18.What are the mean and standard deviation for the standard normal distribution?

                μ = 0, σ = 1

                μ = 0, σ = 0

                μ = 1, σ = 0

                μ = 1, σ = 1

19.A negative value for the correlation coefficient (r) implies a negative value for the slope (b1).

                True

                False

20.The Poisson distribution has only one parameter.

                True

                False

21.Find the probability that either event A or B occurs if the chance of A occurring is .5, the chance of B occurring is .3, and events A and B are independent.

                .15

                .80

                .65

                .85

22.The total sum of squares (SST) will never exceed the regression sum of squares (SSR).

                True

                False

23.A prediction interval for Y is narrower than the corresponding confidence interval for the mean of Y.

                True

                False

24.A biometric security device using fingerprints erroneously refuses to admit 2 in 1,400 authorized persons from a facility containing classified information. The device will erroneously admit 2 in 1,004,000 unauthorized persons. Assume that 95 percent of those who seek access are authorized.

 

If the alarm goes off and a person is refused admission, what is the probability that the person was really authorized? (Round your answer to 5 decimal places.)

 

  Probability         

25.The fracture strength of a certain type of manufactured glass is normally distributed with a mean of 534 MPa with a standard deviation of 13 MPa.

 

(a)         

 

What is the probability that a randomly chosen sample of glass will break at less than 534 MPa? (Round your answer to 2 decimal places.)

 

  Probability         

 

(b)         

 

What is the probability that a randomly chosen sample of glass will break at more than 559 Mpa? (Round your answer to 4 decimal places.)

 

  Probability         

 

(c)          

 

What is the probability that a randomly chosen sample of glass will break at less than 567 MPa? (Round your answer to 4 decimal places.)

 

  Probability

                 

26.Half of a set of the parts are manufactured by machine A and half by machine B. Five percent of all the parts are defective. Two percent of the parts manufactured on machine A are defective.

 

Find the probability that a part was manufactured on machine A, given that the part is defective. (Round your answer to 4 decimal places.)

 

  Probability       

 

27.A student’s grade on an examination was transformed to a z value of 0.67. Assuming a normal distribution, we know that she scored approximately in the top:

                25 percent.

                40 percent.

                50 percent.

                15 percent.

28.Which pairs of events are independent?

  

(a)          P(A) = 0.28, P(B) = 0.14, P(A∩B) = 0.10.

                 

                  A and B are

.

  

(b)          P(A) = 0.15, P(B) = 0.48, P(A∩B) = 0.05.

                 

                  A and B are

.

  

(c)           P(A) = 0.80, P(B) = 0.10, P(A∩B) = 0.08.

                 

                  A and B are

.

29.A large number of applicants for admission to graduate study in business are given an aptitude test. Scores are normally distributed with a mean of 460 and standard deviation of 80. The top 2.5 percent of the applicants would have a score of at least (choose the nearest integer):

                646.

                617.

                606.

                600.

30.A random variable X is best described by a continuous uniform distribution from 20 to 45 inclusive. The mean of this distribution is:

                33.5.

                32.5.

                31.5.

                30.5.