-Compute the sample correlation coefficient between the price and the number of flash drives sold. Also,...

-Compute the sample correlation coefficient between the price and the number of flash drives sold. Also, develop a least-squares estimated regression line.

Price (x)	Units sold (y)
34	4
36	4
32	6
35	5
31	9
38	2
39	1

Expert Solution

Solution :

X	Y	XY	X^2	Y^2
34	4	136	1156	16
36	4	144	1296	16
32	6	192	1024	36
35	5	175	1225	25
31	9	279	961	81
38	2	76	1444	4
39	1	39	1521	1

n	7
sum(XY)	1041.00
sum(X)	245.00
sum(Y)	31.00
sum(X^2)	8627.00
sum(Y^2)	179.00
Numerator	-308.00
Denominator	326.02
r	-0.9447
r square	0.8925

Xbar(mean)	35.0000
Ybar(mean)	4.4286
SD(X)	2.3570
SD(Y)	2.1602

b	-0.8462
a	34.0440

sample correlation coefficient = r = -0.9447

Regression line = 34.0440 - 0.8462 x

orchestra answered 3 years ago

The following data represent the number of flash drives sold per day at a local computer...

The following data represent the number of flash drives sold per day at a local computer shop and their prices. Price (x) Units Sold (y) $34 4 36 4 32 6 35 5 31 9 38 2 39 1 You may use Excel for solving this problem. Compute the sample correlation coefficient between the price and the number of flash drives sold. Develop a least-squares estimated regression line. Compute the coefficient of determination and explain its meaning. Test to...

5. For a random sample of 50 American cities, the linear correlation coefficient between the number...

5. For a random sample of 50 American cities, the linear correlation coefficient between the number of homocides last year and the number of schools in the city was found to be r = 0.653. a. What does this imply? b. Does this suggest that building more schools in a city could lead to higher levels of homocides? Why or why not? c. What is a likely lurking variable? 6. The data below are the first exam scores of 10...

(c) Compute the sample correlation coefficient r for each of the following data sets and show...

(c) Compute the sample correlation coefficient r for each of the following data sets and show that r is the same for both. (Use 3 decimal places.) (i) x 6 1 9 y 4 2 5 (ii)x 4 2 5 y6 1 9

Define correlation coefficient. Describe in your own words the difference between correlation coefficient and coefficient of...

Define correlation coefficient. Describe in your own words the difference between correlation coefficient and coefficient of determination.

Compute the sample correlation coefficient r for each of the following data sets. (Use 3 decimal...

Compute the sample correlation coefficient r for each of the following data sets. (Use 3 decimal places.) (a) x 5 8 9 y 2 2 5 (b) x 2 2 5 y 5 8 9 r(a) = r(b) = x 2 1 2 4 3 y 5 10 9 15 10 (a) Find the linear correlation coefficient r.

Giga Manufacturing Co. manufactures 1 GB flash drives (jump drives). Price and cost data for a...

Giga Manufacturing Co. manufactures 1 GB flash drives (jump drives). Price and cost data for a relevant range extending to 500,000 units per month are as follows: Sales price per unit: (Current monthly sales volume is 400,000 units) $20.00 Variable costs per unit: Direct materials 4.00 Direct labor 6.00 Variable manufacturing overhead 2.00 Variable selling and administrative expenses 2.00 Monthly fixed expenses: Fixed manufacturing overhead $1,600,000 Fixed selling and administrative expenses $1,200,000 Required: What...

6. What is the difference between the correlation coefficient and ?2? Why should the correlation coefficient...

6. What is the difference between the correlation coefficient and ?2? Why should the correlation coefficient be -1 and 1? 7. What is the utility of marginal effects in regression models? How are they obtained? 8. What is heterocedasticity and homocedasticity? Explain how to detect and correct the first.

for a sample of 22 recently sold homes in a large city of correlation between the...

for a sample of 22 recently sold homes in a large city of correlation between the square footage of a house and is selling price house was found to be r = 0.62 a) describe a selling price will generally change as the square footage increases b) assuming there is no outliers in a relationship is linear find R squared and interpret this in context c) his home area was measured in square meters instead of square feet what would...

Data set 2 presents a sample of the number of defective flash drives produced by a small manufacturing company over the last 30 weeks

Data set 2 presents a sample of the number of defective flash drives produced by a small manufacturing company over the last 30 weeks. Use Excel's Analysis ToolPak (or any statistical package that you are comfortable with) to compute the regression equation for predicting the number of defective flash drives over time (in weeks), the correlation coefficient r and the coefficient of determination R2. Submit your statistical output from Excel, which should include values for a slope, y-intercept, regression...

In a two-tailed test for correlation at α = .05, a sample correlation coefficient r =...

In a two-tailed test for correlation at α = .05, a sample correlation coefficient r = 0.42 with n = 25 is significantly different than zero. True or False

Question