13. The data table below shows the number of computers sold at the Bronco Store in a week, based on online advertising. (30 points possible).
Online Ads Computers Sold
2 25
1 10
4 30
1 10
|
2 25
|
a. Calculate the means for both Ads and Computers Sold.
b. Calculate the slope for the estimated regression equation.
The (x-x)(y-y) = 40, just need to calculate denominator.
a)
here,
means for online ads x̅ = Σx / n= 10/5 = 2 ,
mean for somputers sold ȳ = Σy/n = 100/5 = 20
b)
x | y | (x-x̅)² |
2 | 25 | 0.00 |
1 | 10 | 1.00 |
4 | 30 | 4.00 |
1 | 10 | 1.00 |
2 | 25 | 0.00 |
so, denominator = Σ(x-x̅)² = 6.0000
Slope = (x-x)(y-y)/Σ(x-x̅)² = 40/6 = 6.6667
13. The data table below shows the number of computers sold at the Bronco Store in...
Question 47 (20 points) A local tire dealer wants to predict the number of tires sold each month. He believes that the number of tires sold is a linear function of the amount of money invested in advertising. He randomly selects 6 months of data consisting of tire sales (in thousands of tires) and advertising expenditures (in thousands of dollars). Based on the data set with 6 observations, the simple linear regression model yielded the following results. X = 24...
The data below represent commute times (in minutes) and scores on a well-being survey. Commute Time (minutes), x 5 20 25 40 50 84 105 Well-Being Index Score, y 69.2 68.0 67.4 66.6 66.2 65.1 63.3 Given that r = -0.9841, Sx = 35.981, Sy = 1.942. a) Find the equation for the regression line. b) Interpret the slope and y-intercept. c) Find the predicted value of index score when x = 40. Find the residual for the value of...
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 36 32 35 30 38 40 4 Refer to Case 2 data use Excel, Data Analysis, Regression tools and develop a least-squares regression line and explain what the slope of the line indicates y-esimated 29.7857 0.7286x The slope indicates that as the price goes up by $1, the number of units sold goes up...
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 36 32 35 30 38 40 4 Refer to Case 2 data use Excel, Data Analysis, Regression tools and develop a least-squares regression line and explain what the slope of the line indicates y-esimated 29.7857 0.7286x The slope indicates that as the price goes up by $1, the number of units sold goes up...
The table below gives the list price and the number of bids received for five randomly selected items sold through online auctions. Using this data, consider the equation of the regression line, yˆ=b0+b1x, for predicting the number of bids an item will receive based on the list price. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make...
The table below gives the list price and the number of bids received for five randomly selected items sold through online auctions. Using this data, consider the equation of the regression line, yˆ=b0+b1x, for predicting the number of bids an item will receive based on the list price. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make...
5) The table below shows the number of hours spent per week viewing TV (y), and the number of years of education (x) for 10 randomly selected individuals. 10 15 8 y (hours) x(years) 4 20 16 4 15 12 14 11 16 16 18 12 20 10 12 (15 Points) Find the simple linear regression model a) (10 Points) Find 95% confidence interval for B b) (5 Points) c) Calculate R2
The table below gives the list price and the number of bids received for five randomly selected items sold through online auctions. Using this data, consider the equation of the regression line, yˆ=b0+b1x, for predicting the number of bids an item will receive based on the list price. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make...
the table below shows the number of cars sold last month by seven employees at concord motors and thier numbers of year of sales experience experience /sales 1 experience sales 1 8 2 6 2 7 4 14 5 9 6 13 8 10 a regression model is fitted to predict the dependent variable using the independent variable. the model is, y=6.94+0.66x. use the model and predict the y value at x=6 b) what is the error of prediction in...
The following table shows the hot dogs bought from a street vendor over the course of eight days ("Demand"). Also shown is the temperature for each day in degrees Celsius. Complete parts a and b below. Temperature Demand 20 45 9 32 23 36 17 40 8 19 13 22 20 44 22 31 a. calculate the slope and y-intercept for the linear regression equation for these data y=____ + (____)x b. Calculate how many hotdogs would be sold on...