65 68 58 57 71 61 60 67 66 72
60 62 54 57 61 54 55 58 61 55
64 66 56 61 51 83 57 55 58 59
61 55 66 55 58 52 75 67 64 56
55 58 50 62 63 67 57 54 55 63
a. Find the mean, median and mode.
b. Find the range, variance, and standard deviation.
c. Find the lower quartile, upper quartile, and inter-quartile range
2- For the same data set as Problem 1, are there outliers in the data? Justify your conclusion using;
In: Math
Life expectancy in the US varies depending on where an individual lives, reflecting social and health inequality by region. You are interested in comparing mean life expectancies in counties in California, specifically San Mateo County and San Francisco County. Given the data below, answer the following questions.
| Mean life expectancy at birth for males in 2014 | Sample standard deviation | Sample size (n) | |
| San Mateo County |
81.13 years |
8.25 |
101 |
| SF County |
79.34 years |
9.47 |
105 |
1. Calculate the standard error of the mean difference in male life expectancy between the 2 counties, assuming nonequal variance.
2. Calculate a 99% confidence interval for the mean difference in male life expectancy between the two counties. Use the conservative approximation for degrees of freedom.
3. Based on your confidence interval, would you expect the mean difference in male life expectancy to be statistically significant at the α=.01 level? EXPLAIN
In: Math
1. A company is testing how different compensation
plans might affect a salespersons performance. The company takes a
sample of 100 sales representatives and puts 50 on compensation
plan “A” and the other 50 on compensation plan “B”. They do
this for one quarter (3 months) and look at the total sales in
dollars for each salesperson at the end of the quarter. How can we
tell if there is a statistically significant difference between the
two compensation plans.
2. A health club is interested in how the supplements they sell affect weight loss in their clients. Currently the health club is selling three different weight loss supplements (Supplement “X”, Supplement “Y” and Supplement “Z”). Theclub takes a sample of 60 clients and gives a month’s supply of “X” to 20, “Y” to 20 and “Z” to 20. They weigh each member of the sample when they are given the supplement and then again at the end of the month so they can determine total weight loss over the month period. How do we tell if there is any difference between the three supplements with regard to weight loss?
please help me
In: Math
Please show all work. Thank you!
The amount of money requested on home loan applications at America Bank follows normal distribution, with a mean of $180,000 and a standard deviation of $6,000. A loan application is received this morning.
a) What is the probability the amount requested is $190,000 or more?
b) What is the probability the amount requested is between $178,000 and $190,000?
c) What is the probability the amount requested in below $178,000?
d) How much is requested on the largest 5% of the loans?
e) How much is requested on the smallest 5% of the loans?
In: Math
Respond to the following in a minimum of 175 words, please type response:
How can regression modeling be used to understand the association between two variables.
Respond to the following in a minimum of 175 words, please type response:
How can simple regression modeling be extended to understand the relationship among several variables.
In: Math
The weight of male students at a certain university is normally distributed with a mean of 175 pounds with a standard deviation of 7.6 pounds. Find the probabilities.
1. A male student weighs at most 186 pounds.
2. A male students weighs at least 160 pounds.
3. A male student weighs between 165 and 180 pounds.
Please show work. Ideally excel commands would be helpful, but anything would be great!
In: Math
Do larger universities tend to have more property crime? University crime statistics are affected by a variety of factors. The surrounding community, accessibility given to outside visitors, and many other factors influence crime rate. Let x be a variable that represents student enrollment (in thousands) on a university campus, and let y be a variable that represents the number of burglaries in a year on the university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents. x 12.9 30.4 24.5 14.3 7.5 27.7 16.2 20.1 y 27 71 39 23 15 30 15 25
(a) Make a scatter diagram of the data. Then visualize the line you think best fits the data. (Submit a file with a maximum size of 1 MB.) This answer has not been graded yet.
(b) Use a calculator to verify that Σ(x) = 153.6, Σ(x2) = 3385.30, Σ(y) = 245, Σ(y2) = 9795 and Σ(x y) = 5480.1. Compute r. (Enter a number. Round to 3 decimal places.) As x increases, does the value of r imply that y should tend to increase or decrease? Explain your answer. Given our value of r, y should tend to remain constant as x increases. Given our value of r, y should tend to decrease as x increases. Given our value of r, we can not draw any conclusions for the behavior of y as x increases. Given our value of r, y should tend to increase as x increases.
In: Math
In: Math
At one hospital there is some concern about the high turnover of nurses. A survey was done to determine how long (in months) nurses had been in their current positions. The responses (in months) of 20 nurses were as follows. 27 6 9 18 29 40 31 46 16 12 11 27 33 30 32 15 24 35 12 40 Make a box-and-whisker plot of the data. (Select the correct graph.) Find the interquartile range. (Enter an exact number.) IQR =
In: Math
What is the difference between these two problems?
what equation do I use?
In: Math
QUESTion 6
The association between the variables "golf score" and "golf skill"
would be
|
a. |
POSITIVE |
|
|
b. |
NEGATIVE |
|
|
c. |
NEITHER |
QUESTION 7
If the correlation coefficient for a lnear regression is 0.987.
there is sufficient evidence that a linear relationship exists
between the x and y data
|
a. |
TRUE |
|
|
b. |
FALSE |
QUESTION 8
If the correlation coefficient for a lnear regression is -0.932.
there is sufficient evidence that a linear relationship exists
between the x and y data
|
a. |
TRUE |
|
|
b. |
FALSE |
QUESTION 9
A data point that lies statistically far from the regression line
is a potential
|
a. |
response variable |
|
|
b. |
predictor variable |
|
|
c. |
extrapolated variable |
|
|
d. |
outlier |
QUESTION 10
|
a. |
response variable |
|
|
b. |
the predictor variable |
|
|
c. |
the extrapolted variable |
|
|
d. |
an outlier |
QUESTION 11
If the correlation coefficient for a linear regression is 1.00.
there is solid proof that a true cause-effect relationship exists
between the x and y data
|
a. |
TRUE |
|
|
b. |
FALSE |
QUESTION 12
|
a. |
The x and y variables appear to be mostly unrelated |
|
|
b. |
The x and y variables appear to have a strong relationship |
|
|
c. |
The x and y variables appear to have no meaningful linear relationship but may be related by some nonlinear function |
|
|
d. |
The x and y variables have a strong linear relationship |
In: Math
Given a normal distribution with (mean) μ= 50 and (standard deviation) σ = 4, what is the probability that
NOTE: I'd like to learn how to do this in the shortest way possible on ti 84 plus calculator.
a) x>43
b) x<42
c) x>57.5
d) 42 <x<48
e) x<40 or x>55
f) 5% of the values are less than what X value?
g) 60% of the values are between what two X values (symmetrically distributed around the mean)?
h) 85% of the values will be above what X value?
In: Math
Epsilon Airlines services predominately the eastern and southeastern United States. A vast majority of Epsilon’s customers make reservations through Epsilon’s website, but a small percentage of customers make reservations via phone. Epsilon employs call-center personnel to handle these reservations along with any problems with the website reservation system and for the rebooking of flights for customers if their plans change or their travel is disrupted. Staffing the call center appropriately is a challenge for Epsilon’s management team. Having too many employees on hand is a waste of money, but having too few results in very poor customer service and the potential loss of customers.
Epsilon analysts have estimated the minimum number of call-center employees needed by day of week for the upcoming vacation season (June, July, and the first two weeks of August). These estimates are as follows:
| Day | Minimum Number of Employees Needed |
| Monday | 75 |
| Tuesday | 50 |
| Wednesday | 45 |
| Thursday | 60 |
| Friday | 90 |
| Saturday | 75 |
| Sunday | 45 |
The call-center employees work five consecutive days and then have two consecutive days off. An employee may start work any day of the week. Each call-center employee receives the same salary. Assume that the schedule cycles and ignore start-up and stopping of the schedule. Develop a model that will minimize the total number of call-center employees needed to meet the minimum requirements. Find the optimal solution. Give the number of call-center employees that exceed the minimum required. Use a software package LINGO or Excel Solver. If your answer is zero, enter "0".
Let Xi = the number of call center employees who start work on day i (i = 1 = Monday, i = 2 = Tuesday…)
| Min | X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ |
| s.t. | |||||||||||||||
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X2______ | + | X2______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1______ | + | X2______ | + | X3______ | + | X4______ | + | X5______ | + | X6______ | + | X7______ | ≥ | ______ | |
| X1, X2, X3, X4, X5, X6, X7 ≥ 0 | |||||||||||||||
Solution:
| X1 | = | ______ |
| X2 | = | ______ |
| X3 | = | ______ |
| X4 | = | ______ |
| X5 | = | ______ |
| X6 | = | ______ |
| X7 | = | ______ |
Number of excess employees:
| Monday | = | ______ |
| Tuesday | = | ______ |
| Wednesday | = | ______ |
| Thursday | = | ______ |
| Friday | = | ______ |
| Saturday | = | ______ |
| Sunday | = | ______ |
Total Number of Employees = ______
In: Math
Do bonds reduce the overall risk of an investment portfolio? Let x be a random variable representing annual percent return for Vanguard Total Stock Index (all stocks). Let y be a random variable representing annual return for Vanguard Balanced Index (60% stock and 40% bond). For the past several years, we have the following data.
| x: |
28 |
0 |
38 |
25 |
17 |
33 |
28 |
−18 |
−21 |
−19 |
| y: |
18 |
−8 |
28 |
18 |
8 |
15 |
12 |
−9 |
−9 |
−4 |
Compute a 75% Chebyshev interval around the mean for x values and also for y values. (Round your answers to two decimal places.)
In: Math
Romans Food Market, located in Saratoga, New York, carries a variety of specialty foods from around the world. Two of the store’s leading products use the Romans Food Market name: Romans Regular Coffee and Romans DeCaf Coffee. These coffees are blends of Brazilian Natural and Colombian Mild coffee beans, which are purchased from a distributor located in New York City. Because Romans purchases large quantities, the coffee beans may be purchased on an as-needed basis for a price 10% higher than the market price the distributor pays for the beans. The current market price is $0.47 per pound for Brazilian Natural and $0.62 per pound for Colombian Mild. The compositions of each coffee blend are as follows:
| Blend | ||
|---|---|---|
| Bean | Regular | DeCaf |
| Brazilian Natural | 75% | 40% |
| Colombian Mild | 25% | 60% |
Romans sells the Regular blend for $3.60 per pound and the DeCaf blend for $4.40 per pound. Romans would like to place an order for the Brazilian and Colombian coffee beans that will enable the production of 1000 pounds of Romans Regular coffee and 500 pounds of Romans DeCaf coffee. The production cost is $0.80 per pound for the Regular blend. Because of the extra steps required to produce DeCaf, the production cost for the DeCaf blend is $1.05 per pound. Packaging costs for both products are $0.25 per pound. Formulate a linear programming model that can be used to determine the pounds of Brazilian Natural and Colombian Mild that will maximize the total contribution to profit.
| Let | BR = pounds of Brazilian beans purchased to produce Regular |
| BD = pounds of Brazilian beans purchased to produce DeCaf | |
| CR = pounds of Colombian beans purchased to produce Regular | |
| CD = pounds of Colombian beans purchased to produce DeCaf |
If required, round your answers to three decimal places. For subtractive or negative numbers use a minus sign even if there is a plus sign before the blank. (Example: -300)
| Max | ______BR | + | ______BD | + | ______CR | + | ______CD | ||
| s.t. | |||||||||
| Regular blend | ______BR | + | ______CR | = | ______ | ||||
| DeCaf blend | ______BD | + | ______CD | = | ______ | ||||
| Regular production | ______BR | ______CR | = | ______ | |||||
| DeCaf production | ______BD | + | ______CD | = | ______ | ||||
| BR, BD, CR, CD ≥ 0 | |||||||||
What is the optimal solution and what is the contribution to profit? If required, round your answer to the nearest whole number.
Optimal solution:
| BR = ______ |
| BD = ______ |
| CR = ______ |
| CD = ______ |
If required, round your answer to the nearest cent.
Value of the optimal solution = $ ______
In: Math