Compute the coefficient of correlation

Assignment Help Basic Statistics

Reference no: EM132122184

Question 1

Below you are given the examination scores of 20 students (data set also provided in accompanying MS Excel file).

52	99	92	86	84
63	72	76	95	88
92	58	65	79	80
90	75	74	56	99

a. Construct a frequency distribution, cumulative frequency distribution, relative frequency distribution, cumulative relative frequency distribution and percent frequency distribution for the data set using a class width of 10.

b. Construct a histogram showing the percent frequency distribution of the examination scores. Comment on the shape of the distribution.

Question 2

Shown below is a portion of a computer output for a regression analysis relating supply (Y in thousands of units) and unit price (X in thousands of dollars).

ANOVA
	df	SS
Regression	1	354.689
Residual	39	7035.262
	*Coefficients*	*Standard Error*
Intercept	54.076	2.358
X	0.029	0.021

a. What has been the sample size for this problem?
b. Determine whether or not supply and unit price are related. Use α = 0.05.
c. Compute the coefficient of determination and fully interpret its meaning. Be very specific.

d. Compute the coefficient of correlation and explain the relationship between supply and unit price.
e. Predict the supply (in units) when the unit price is $50,000.

Question 3

Allied Corporation wants to increase the productivity of its line workers. Four different programs have been suggested to help increase productivity. Twenty employees, making up a sample, have been randomly assigned to one of the four programs and their output for a day's work has been recorded. You are given the results below (data set also provided in accompanying MS Excel file).

Program A	Program B	Program C	Program D
150	150	185	175
130	120	220	150
120	135	190	120
180	160	180	130
145	110	175	175

a. Construct an ANOVA table.
b. As the statistical consultant to Allied, what would you advise them? Use a .05 level of significance.

Question 4

A company has recorded data on the weekly sales for its product (y), the unit price of the competitor's product (x1), and advertising expenditures (x2). The data resulting from a random sample of 7 weeks follows. Use Excel's Regression Tool to answer the following questions (data set also provided in accompanying MS Excel file).

Week	Price	Advertising	Sales
1	.33	5	20
2	.25	2	14
3	.44	7	22
4	.40	9	21
5	.35	4	16
6	.39	8	19
7	.29	9	15

a. What is the estimated regression equation? Show the regression output.
b. Determine whether the model is significant overall. Use α = 0.10.
c. Determine if competitor's price and advertising is individually significantly related to sales. Use α = 0.10.

d. Based on your answer to part (c), drop any insignificant independent variable(s) and re-estimate the model. What is the new estimated regression equation?

e. Interpret the slope coefficient(s) of the model from part (d).

Reference no: EM132122184

Questions Cloud

What is information security : What is Information Security? How does the proper application of Information Security can reduce risk?

What responsibilities does an information systems department : What responsibilities does an information systems department have in ensuring the security of these assets?

Calculate the probability of selecting a random sample : Calculate the probability of selecting a random sample of 225 observations with a sample proportion of 0.54 or greater, if the sample population has a populatio

How improve the efficiency of the overall healthcare system : What should (can) senior health policy makers do to improve the efficiency of the overall healthcare system

Compute the coefficient of correlation : HI6007 - Compute the coefficient of determination and fully interpret its meaning. Be very specific - Determine whether or not supply and unit price are related

Discuss the main findings and their implications : Begin the review by defining the objective of the paper. Introduce the reader to your focal question. What is this question intended to address?

What percentage of yearly returns are at or above below : You are allowed to use Excel. What percentage of yearly returns are at or above below the 10th percentile?"

Do you believe that those guidelines provide fair sentencing : State legislatures began adopting sentencing guidelines that legally limited the judges' discretion.

What weight represents the 49th percentile : Use the Normal model ?N(1107?,56) for the weights of steers. A) What weight represents the 49th Percentile?

User Account

All Pages