Questions
Discuss the differences between histograms, relative frequency histograms, time series graphs, and stem and leaf displays.

Discuss the differences between histograms, relative frequency histograms, time series graphs, and stem and leaf displays.

In: Math

A _________________ is an important characteristic related to the response variable which, when unaccounted for, may...

A _________________ is an important characteristic related to the response variable which, when unaccounted for, may lead researchers to false conclusions about cause and effect.

Question 2 options:

A)

Confounder

B)

Placebo

C)

Bias

D)

Paradox

E)

Confidence Interval

In a double-blind experiment conducted to study the effectiveness of a new drug to relieve the common cold, a participant was given a sugar pill. After taking the pill, she finds she can breathe more easily, and her condition substantially improved. Which of the following describes this phenomenon?

Question 4 options:

A)

Simpson’s Paradox

B)

Equivalence Principle

C)

Placebo Effect

D)

Selection Bias

E)

Confounding

Question 5 (1 point)

Statistics can be an ‘art’ as different statisticians may use different methods of analysis in answering questions pertaining to a study.

Question 5 options:

A) True
B) False

Question 6 (1 point)

Researchers want to test a new type of surgical procedure. Individuals are randomly placed in one of two groups. Ten individuals receive the new surgery, while the other 10 individuals receive the old surgery as a control. The participants do not know which surgical procedure they receive. Researchers are aware of which individuals are placed in each group. Which of the following characteristics of a controlled experiment has not been satisfied?

Question 6 options:

A)

Comparison of treatment and control groups

B)

Randomization

C)

Blinding

D)

Double-blinding

E)

Selection bias

Question 7 (1 point)

Which of the following would not necessarily be considered one of the four principles of good practice in a controlled experiment?

Question 7 options:

A)

Make a comparison (treatment and control group)

B)

Randomize the group membership of the subjects

C)

Make sure to pull equally from younger and older individuals

D)

Make the experiment blind

E)

Make the experiment double-blind

In: Math

I have a normal process (Anderson-Darling pvalue=.54   and skew=.3. The median The R chart is out...

I have a normal process (Anderson-Darling pvalue=.54   and skew=.3. The median

The R chart is out of control (1 outlier). This means that the process variability is unstable, and the control limits on the xbar chart are unreliable. The process is not stable over time. What if anything does this have to do with choosing the center of the distribution? Use the median in this instance. Outliers will not affect median as much as the mean. That is my best guess.

In: Math

Would you please demonstrate to me how to create dataset A and dataset B, where dataset...

Would you please demonstrate to me how to create dataset A and dataset B,
where dataset A has a larger range but smaller standard deviation than
dataset B. Then the reverse where data set A has a smaller range and larger standard deviation than data set B.

In: Math

Suppose you own a fish restaurant and you believe that the demand for sea bass is...

  1. Suppose you own a fish restaurant and you believe that the demand for sea bass is distributed normally (that is, follows the bell-shaped curve) with a mean of 12 pounds and a standard deviation of 3.2. In summary, we express this as N(12,3.2).

    1a. The notation N(12,3.2) means that

    The mean (average) is 3.2 and the standard deviation is 12

    The mean is 12 and the standard deviation is 3.2 and the data follows a bell shape curve

    The mean is 12 and the standard deviation is 3.2 and the data does not follow a bell shape curve

10 points

Question 2

  1. What is the z-score for 20 pounds of sea bass? You find the z-score by calculating (x-mean)/standard deviation

    0.0062

    2.50

    0.9938

    0.25

10 points

Question 3

  1. The number inside Table A associated with 2.50 is

    2.50

    0.0062

    0.9938

    0.25

10 points

Question 4

  1. The number in the table represents that area to the

    Right

    Left

10 points

Question 5

  1. So 0.9938 is the area associated with a Z score of

    2.50 or more

    2.50 or less

10 points

Question 6

  1. The probability that you will need 20 pounds or more of sea bass is

    0.25

    0.0062

    0.9938

    2.50

10 points

Question 7

  1. What is the z-score for 15 pounds of sea bass

    0.94

    0.8264

    0.06

    -0.94

10 points

Question 8

  1. What is the number inside table A associated with 0.94

    0.8264

    0.1736

    0.94

10 points

Question 9

  1. So 0.8264 is the area associated with a Z score of

    0.94 or less

    0.94 or more

10 points

Question 10

  1. The probability that you will need 15 pounds of sea bass or less is

    0.1736

    0.94

    0.8264

10 points

Question 11

  1. What is the probability that you will need between 15 and 20 pounds of sea bass

    0.94

    0.8264

    0.1674

10 points

Question 12

  1. What is the z-score associated with the 95th percentile of the standard normal curve

    0.95

    1.65

    1.28

10 points

Question 13

  1. How many pounds of sea bass are needed for the 95th percentile of sea bass demand

    1.65

    7.28

    17.28

In: Math

"You ask students to identify European countries on a map. On average students will identify 10%...

"You ask students to identify European countries on a map. On average students will identify 10% of the countries correctly. A similar test for US states indicates a 45% success rate. Asking students to identify 7 European countries and 3 US states, what is the chance that students will correctly identify at least 50% of the countries/states?"

"You have a set of 100 batteries. 13 of these batteries are defective. Testing 25 batteries, what is the probability to find 3 or more of the 25 batteries failing?"

In: Math

The true, unobserved population mean commute distance among all urban planners working in the Melbourne Metropolitan...

  1. The true, unobserved population mean commute distance among all urban planners working in the Melbourne Metropolitan Area (μ) is 22km, with σ=15. You conduct a survey of 144 planners and find that the sample means commute distance (X-bar) is 25km (12 points).

  1. Describe two possible sources of bias that could have produced this high estimate? (4 points)
  2. Is this sample mean impossible if no bias is introduced from your sampling process or survey questions? Why or why not? (4 points)
  3. Presuming that no bias is introduced by your sampling and survey, what is the probability that you will draw this sample? Show your work. (4 points)

In: Math

Genetic theory predicts that, in the second generation of a cross of sweet pea plants, flowers...

Genetic theory predicts that, in the second generation of a cross of sweet pea plants, flowers will be either red or white, with each plant having a 25% chance of producing red flowers. Flower colours of separate plants are independent. Let X be the number of plants with red flowers out of 20 plants selected at random from the second generation of this cross. (a) What is the probability distribution of X? [3] (b) Calculate: (i) the mean and standard deviation of X. [3] (ii) P( X > 8) [2] (iii) P( 4 ≤ X ≤ 10) [2] (c) If only 3 of the 20 plants had red flowers, would this be an unusual sample? Calculate a probability and use it to justify your answer

In: Math

Why is Levene’s test a useful test for factorial ANOVA? It looks to see if there...

Why is Levene’s test a useful test for factorial ANOVA?
It looks to see if there are any significant differences within group variables.
It looks to see if there are any significant differences within group variances.
It looks to see if there are any significant differences between group variances.
None of the above .

In: Math

Problem 4: A large firm uses three different types (A, B, and C) of raw materials...



Problem 4: A large firm uses three different types (A, B, and C) of raw materials to manufacture its product. Previous records show that 25% of the manufactured products are produced using material A, 50% using material B, and 25% using material C. If it is known that 5% of the product made with material A are defective, 2% made with material B are defective, and 5% made with C are defective.
What is the probability that a product selected at random from this firm will be defective?
If a product selected at random from this firm is found to be defective, what is the probability that it was made from material A.

In: Math

Question 2 Frasers Logistics operates a large fleet of trucks that transport goods on behalf of...

Question 2

Frasers Logistics operates a large fleet of trucks that transport goods on behalf of their clients. The trucks undergo regular scheduled maintenance as well as unscheduled maintenance when a problem occurs.   Data about the maintenance expense is collected continuously and recorded by the admin staff of Frasers.   Frasers do believe in updating their fleet of trucks on a continuous basis and hence has trucks in operation of various ages.   They suspect that both the age of the truck as well as the distance covered in km in a particular year will have an impact on the maintenance costs of the trucks. The data for a particular size truck has been collected and is shown in the table below.

Truck

Expense (E)

Distance in km (K)

Age in years (A)

Truck

Expense (E)

Distance in km (K)

Age in years (A)

1

3529.80

16800

2

13

12201.75

47040

8

2

4563.75

17280

1

14

6409.80

43560

1

3

8137.95

37840

4

15

10899.75

20320

10

4

9294.15

39840

9

16

2695.20

14880

3

5

12588.15

49440

6

17

3402.15

12000

3

6

11903.25

44160

8

18

6540.60

31680

5

7

3471.90

12480

1

19

3844.50

36785

2

8

11993.70

47040

7

20

12056.70

47520

7

9

12157.95

26560

9

21

11266.80

46560

7

10

13732.95

48000

11

22

5701.65

31200

5

11

2623.95

10560

3

23

13628.40

50400

10

12

5530.80

21600

2

The Expense column reflects the full maintenance expense for that particular truck during the past financial year, the Distance column reflects the distance in km that the truck covered in the past financial year and the Age column reflects the age of the truck.

Use the data in the sheet named “Frasers” and use Excel and the Data Analysis add-in to perform linear regression analysis on the data to determine whether direct distance travelled (K) or age (A) or both should be used for estimating future maintenance expenditure. Specifically answer the following questions:

  1. Decide which linear regression model (with distance travelled (K) or age (A) or both as independent variable) is the better model and motivate your selection.

The remaining answers must be based on the model that you have selected.

  1. What is the total variation in “Expense” that is explained by the independent variable(s) that you have selected.
  2. Is the overall regression model statistically significant? Test at the 5% level of significance using the model that you have selected in a. For this test formulate the appropriate null and alternative hypothesis, determine the region of acceptance, use the appropriate test statistic and draw the statistical and management conclusions.
  3. Is the distance travelled (K) variable significant at the 5% level of significance? For this test use the model that you have selected in a. and formulate the appropriate null and alternative hypothesis, determine the region of acceptance, use the appropriate test statistic and draw the statistical and management conclusions.
  4. Interpret the intercept of the regression equation.
  5. Write down the linear regression equation in algebraic format using E for expense, K for the distance travelled and A for the age of the truck.

In: Math

The expected number of births at a rural hospital is one per day. Assume that births...

The expected number of births at a rural hospital is one per day. Assume that births occur independently and at a constant rate.

  1. Use R to the draw the pmf of the number of births per day at this hospital.

  2. Find the probability of observing at least 3 births in a day.

  3. Find the probability of observing at most 5 births in a week.

  4. At a larger hospital, the expected number of births per day is 17.4. Assume that births occur independently and at a constant rate. On average, how long do we have to wait until a birth at this hospital?

  5. What is the distribution of the total number of births per day at both of these two hospitals (the sum of births at each of the hospitals)? State any assumptions that you are making.

In: Math

Test the hypothesis using the​ P-value approach. Be sure to verify the requirements of the test....

Test the hypothesis using the​ P-value approach. Be sure to verify the requirements of the test.

Upper H 0 : p equals 0.58 versus Upper H 1 : p less than 0.58H0: p=0.58 versus H1: p<0.58

n equals 150 comma x equals 81 comma alpha equals 0.01n=150, x=81, α=0.01

Is

np 0 left parenthesis 1 minus p 0 right parenthesis greater than or equals 10np01−p0≥10​?

No

Yes

In: Math

it is claimed that the following data comes from a Poisson distribution with mean 5. test...

it is claimed that the following data comes from a Poisson distribution with mean 5.

test the claim at a 0.01 level of significance

score < = 3 4 5 6 > = 7 total
frequency 6 9 10 7 4 36

In: Math

Please answer the following: United Dairies, Inc., supplies milk to several independent grocers throughout Dade County,...

Please answer the following: United Dairies, Inc., supplies milk to several independent grocers throughout Dade County, Florida. Managers at United Dairies want to develop a forecast of the number of half gallons of milk sold per week. Sales data for the past 12 weeks are:

Week

Sales

1

2,750

2

3,100

3

3,250

4

2,800

5

2,900

6

3,050

7

3,300

8

3,100

9

2,950

10

3,000

11

3,200

12

3,150

1. Compute four-week and five-week moving averages for the time series.

    1. Compute the MSE for the four-week and five-week moving average forecasts.
    2. What appears to be the best number of weeks of past data (three, four, or five) to use in the moving average computation? The MSE for three weeks is 23527.78
  1. Show the exponential smoothing forecasts using α = 0.1.
    1. Applying the MSE measure of forecast accuracy, would you prefer a smoothing constant of α=0.1 or α= 0.2 for the United Dairies sales time series?
    2. Are the results the same if you apply MAE as the measure of accuracy?
    3. What are the results if MAPE is used?
  2. Use exponential smoothing with a α = 0.4 to develop a forecast of demand for week 13. What is the resulting MSE?

PLEASE USE EXCEL AND ANSWER EACH PART OF THE QUESTION. THANKS !

ANSWER- THAT'S WHAT I GOT SO FAR:

Average=> 117.19 19,238.28 3.8% 101.43 16300.00 3.21%
MAE MSE MAPE MAE MSE MAPE

In: Math