Describe the potential advantages and disadvantages of incorporating additional explanatory variables in a multiple regression model.
In: Math
The following time series shows the sales of a particular product over the past 12 months. can be found in the below excel file.
https://drive.google.com/file/d/1gIpr0IBYUGgCIRSO7g3mqZ84F89vJU_P/view?usp=sharing
1. Using the three-month moving average, what is the Mean Squared Error (MSE)?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
2. Using the three-month moving average, what is the forecast for month 13 ?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
3. Using the exponential smoothing approach for α .3 or .7, what is the Mean Squared Error (MSE)?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
4. Using the exponential smoothing approach for , .3 or .7, what is the forecast for month 13?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
5. Using the exponential smoothing approach for , .5 or .5, what is the Mean Squared Error (MSE)?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
6. Using the exponential smoothing approach for , .5 or .5, what is the forecast for month 13?
(Round your answer to 2 decimal places. Negative values should be indicated by a minus sign.)
7. Does a smoother constant of .3 or .5 provide more accurate forecasts based on MSE ?
.3 | |
.5 |
In: Math
In: Math
A guidance counselor claims that high school students in a college preparation program have higher ACT scores than those in a general program. The sample mean ACT score for 49 high school students who are in a college preparation program is 22.2 and the sample standard deviation is 4.8. The sample mean ACT score for 44 high school students who are in a general program is 20.0 and the sample standard deviation is 5.4.
Use an 8% level of significance to conduct test the guidance counselor’s claim. Assume the distribution of ACT scores for both programs are approximately normally distributed. Assume that σcollege prep2 ‡ σgeneral2 .
H0: Level of significance (α): α =
HA: Type test: two-tailed left tail right tail
Specify the random variable and distribution to be used in this hypothesis test.
Calculate the p-value Draw a graph and show the p-value
Show your work and any calculator functions used.
Compare the p-value with α Decide to Reject or Fail to reject the null hypothesis
Conclusion. State your results in non-technical terms.
In: Math
I have extra columns with data showing up in my pivot table. How can I get rid of the extra columns?
In: Math
Car battery
The mileage of a car battery is exponentially distributed with a mean value of 10000 km.
(a) What is the probability of a 5000 km trip without replacement of the battery?
(b) What is the maximum length of travel that can be terminated with 90% probability without replacing the battery?
(c) Determine the median, the mean and the variance of the mileage of the battery
In: Math
Assume that women's heights are normally distributed with a mean given by μ=63.5 in, and a standard deviation given by σ=2.1 in.
(a) If 1 woman is randomly selected, find the probability that her height is less than 64 in.
(b) If 44 women are randomly selected, find the probability that they have a mean height less than 64
In: Math
Income
Person |
(Yi) |
F(Yi) |
1 | 79.6 | 0.1 |
2 | 138.7 | 0.2 |
3 |
173.1 |
0.3 |
4 |
187.8 |
0.4 |
5 |
201.3 |
0.5 |
6 |
226.6 |
0.6 |
7 |
247.4 |
0.7 |
8 |
289.2 |
0.8 |
9 |
322.8 |
0.9 |
10 |
587.9 |
1 |
A. The mean or average of the ranked above data for a village in Peru is:
a. $245.44
b. $345.44
c. $123.44
d. $200.56
B. Suppose that the covariance between the ranked income and the cumulative distribution of income is 33.24. The Gini coefficient for this village is approximately:
a. .212
b. .223
c. .271
d. .281
In: Math
he final exam grade of a statistics class has a skewed distribution with mean of 78 and standard deviation of 7.8. If a random sample of 30 students selected from this class, then what is the probability that average final exam grade of this sample is between 75 and 80?
In: Math
Part 1
A company produces steel rods. The lengths of the steel rods are
normally distributed with a mean of 198.9-cm and a standard
deviation of 2.3-cm. For shipment, 22 steel rods are bundled
together.
Find P52, which is the average length
separating the smallest 52% bundles from the largest 48%
bundles.
P52 = _____ cm
Part 2
Scores for a common standardized college aptitude test are
normally distributed with a mean of 513 and a standard deviation of
96. Randomly selected men are given a Test Prepartion Course before
taking this test. Assume, for sake of argument, that the test has
no effect.
If 1 of the men is randomly selected, find the probability that his
score is at least 616.
P(X > 616) = __________
If 5 of the men are randomly selected, find the probability that
their mean score is at least 616.
P(M > 616) = __________
Part 3
A population of values has a normal distribution with μ=152.8
and σ=59.7. You intend to draw a random sample of size n=211.
Find the probability that a single randomly selected value is
between 140.9 and 164.3.
P(140.9 < X < 164.3) = __________
Find the probability that a sample of size n=211 is randomly
selected with a mean between 140.9 and 164.3.
P(140.9 < M < 164.3) = _____________
Part 4
A population of values has a normal distribution with μ=164.8
and σ=37.2. You intend to draw a random sample of size n=108.
Find the probability that a sample of size n=108 is randomly
selected with a mean between 154.1 and 169.8.
P(154.1 < M < 169.8) = _________
Part 5
A population of values has a normal distribution with μ=143.9
and σ=89.6. You intend to draw a random sample of size n=217.
Find the probability that a single randomly selected value is
between 133 and 162.1.
P(133 < X < 162.1) = ________
Find the probability that a sample of size n=217 is randomly
selected with a mean between 133 and 162.1.
P(133 < M < 162.1) = _______________
Part 6
A population of values has a normal distribution with μ=179 and
σ=98.2. You intend to draw a random sample of size n=75.
Find the probability that a sample of size n=75 is randomly
selected with a mean less than 181.3.
P(M < 181.3) = ___________
In: Math
Twelve dogs from three different breeds (basenji, Shetland sheepdog, beagle) were either indulged or disciplined between the third and eight weeks of their lives. The indulged animals were encouraged in play, aggression, and climbing on their caretaker. In contrast, the disciplined dogs were retrained to their handler’s lap, taught to sit, stay, come, and so on. The indulged-disciplined treatment was inspired by reports that overindulged children cannot often inhibit their impulses in structured situations. Each dog was taken into a room with a bowl of meat. The dog was hungry but the handler prevented it from eating for 3 minutes by hitting on the rump with a newspaper and shouting ‘no’. The handler left the room and the length of time it took the dog to begin eating the meat was recorded. Presumably, the indulged dog should go to the food more quickly than the disciplined dogs.
Basenjis |
Shetlands |
Beagles |
|
Indulged |
1 |
7 |
9 |
4 |
10 |
7 |
|
3 |
10 |
10 |
|
1 |
9 |
10 |
|
2 |
6 |
8 |
|
2 |
8 |
9 |
|
Disciplined |
5 |
9 |
2 |
1 |
9 |
6 |
|
4 |
8 |
3 |
|
1 |
10 |
4 |
|
2 |
5 |
5 |
|
3 |
8 |
3 |
a. State the hypotheses for each of the three separate tests included in the two-factor ANOVA.
b. Use SPSS or manual calculation to test the significance of main and the interaction effects.
c. Present the effect size for each of the three tests
In: Math
Determine whether the value is a discrete random variable, continuous random variable, or not a random variable.
a. The number of bald eagles in a countrynumber of bald eagles in a country
b. The number of points scored during a basketball gamenumber of points scored during a basketball game
c. The response to the survey question "Did you smoke in the last week question mark "response to the survey question "Did you smoke in the last week?"
d. The number of free dash throw attempts before the first shot is madenumber of free-throw attempts before the first shot is made
e. The square footage of a housesquare footage of a house
f. The height of a randomly selected giraffeheight of a randomly selected giraffe
a. Is the
number of bald eagles in a countrynumber of bald eagles in a country
a discrete random variable, a continuous random variable, or not a random variable?
A.
It is a
continuouscontinuous
random variable.
B.
It is a
discretediscrete
random variable.
C.
It is not a random variable.
b. Is the
number of points scored during a basketball gamenumber of points scored during a basketball game
a discrete random variable, a continuous randomvariable, or not a random variable?
A.
It is a
continuouscontinuous
random variable.
B.
It is a
discretediscrete
random variable.
C.
It is not a random variable
c. Is the
response to the survey question "Did you smoke in the last week question mark "response to the survey question "Did you smoke in the last week?"
a discrete random variable, a continuous random variable, or not a random variable?
A.
It is a continuous random variable.
B.
It is a discrete random variable.
C.
It is not a random variable.
d. Is the
number of free dash throw attempts before the first shot is madenumber of free-throw attempts before the first shot is made
a discrete random variable, a continuous random variable, or not a random variable?
A.
It is a
discretediscrete
random variable.
B.
It is a
continuouscontinuous
random variable.
C.
It is not a random variable.
e. Is the
square footage of a housesquare footage of a house
a discrete random variable, a continuous random variable, or not a randomvariable?
A.
It is a
continuouscontinuous
random variable.
B.
It is a
discretediscrete
random variable.
C.
It is not a random variable.
f. Is the
height of a randomly selected giraffeheight of a randomly selected giraffe
a discrete random variable, a continuous random variable, or not a random variable?
A.
It is a
continuouscontinuous
random variable.
B.
It is a
discretediscrete
random variable.
C.
It is not a random variable.
In: Math
The following bivariate data set contains an outlier.
x | y |
---|---|
53.3 | 151.7 |
37.1 | -307.3 |
44.6 | -469.7 |
47 | -475.2 |
68.4 | 292.5 |
50.3 | 383.5 |
55.7 | -1180.8 |
30.7 | 223.7 |
60.6 | -600.8 |
39.9 | -152.6 |
49.3 | -335.2 |
50.1 | 590.1 |
54.9 | 99 |
63.1 | 243.5 |
181.5 | -6493.5 |
What is the correlation coefficient with the
outlier?
rw = (Round to three decimal
places)
What is the correlation coefficient without the
outlier?
rwo = (Round to three decimal
places)
In: Math
8.29 In a survey of 1,003 adults concerning complaints about restaurants, 732 complained about dirty or ill-equipped bathrooms and 381 complained about loud or distracting diners at other tables.
a. Construct a 95% confidence interval estimate for the population proportion of adults who complained about dirty or ill-equipped bathrooms )
b. Construct a 95% confidence interval estimate for the population proportion of adults who complained about loud or distracting diners at other tables.
c. How would the manager of a chain of restaurants use the results of (a) and (b)?
In: Math