Question

In: Operations Management

The quarterly sales data (number of book sold) for Christian book over the past three years...

The quarterly sales data (number of book sold) for Christian book over the past three years in California follow: (You can use Excel to compute the equation)

Quarter

Year 1

Year 2

Year 3

1

1650

1700

1750

2

950

800

1200

3

2600

2950

3100

4

2700

2450

2850
  1. Construct a line graph showing the pattern of Christian book sales. Please make sure ‘time/quarter’ is represented by the horizontal line and ‘quarterly sale’ is represented by the vertical line. What type of pattern exists in the data?

  1. Use the following dummy variables to develop an estimated regression equation to account for any seasonal effects in the data: Quarter1=1 if the sales data point is in Quarter 1, otherwise Quarter 1=0; Quarter 2=1 if the sales data point is in Quarter 2, otherwise, Quarter 2=0; Quarter 3=1 if the sales data point is in Quarter 3, otherwise Quarter 3=0. 3.

  1. Compute the quarterly forecasts for next year.

  1. 4. Let t=1 to refer to the observation in quarter 1 of year 1; t=2 to refer to the observation in quarter 2 of year 1;,,,, and t=12 to refer to the observation in quarter 4 of year 3. Using the dummy variables defined in part (b) and t, develop an estimated regression equation to account for seasonable effects and any linear trend in the time series. Based upon the seasonal effects in the data and linear trend, compute the quarterly forecasts for next year.

Solutions

Expert Solution

Part a) Following is the required chart:

Following pattern is observed by the above chart: Quarter 2 is having the least sales in all the years follwed by quarter 1 then quarter 3 and then quarter 4.

Part b) Following is the formulated data as per requirement and the ANOVA table:

Required Equation from above regression model is :

Sales = 2666.67 - 966.67*Q1 - 1683.34*Q2 + 216.67*Q3

Next year forecasts are as follows:

Quarter 1 = 1700 units

Quarter 2 = 983 units

Quarter 3 = 2883 units

Quarter 4 = 2667 units

Part c) Following is the formulated data as per requirement and the ANOVA table:

Required Equation from above regression model is :

Sales = 2416.67 + 31.25*t - 872.92*Q1 - 1620.84*Q2 + 247.92*Q3

Next year forecasts are as follows:

Quarter 1 = 1950  units

Quarter 2 = 1233 units

Quarter 3 = 3133 units

Quarter 4 = 2917 units

keosha answered 16 hours ago
Next > < Previous

Related Solutions

The quarterly sales data (number of book sold) for Christian book over the past three years...
The quarterly sales data (number of book sold) for Christian book over the past three years in California follow:     Year 1               Year 2               Year 3   1690              1800                  1850   940                 900                   1100   2625              2900                  2930   2500             2360                   2615 1. Construct a time series plot. What type of pattern exists in the data? This was not shown in the WebEx example I provided. But you can simply create this graph in Excel (Go to INSERT and look for charts under INSERT...
The quarterly sales data (number of copies sold) for a college textbook over the past three...
The quarterly sales data (number of copies sold) for a college textbook over the past three years follow: Year Quarter Sales 1 1 1690 2 940 3 2625 4 2500 2 1 1800 2 900 3 2900 4 2360 3 1 1850 2 1100 3 4 2930 2615 a. Construct a time series plot. What type of pattern exists in the data?   b. Show the four‐quarter and centered moving average values for this time series. c. Compute the seasonal and...
The quarterly sales data (number of copies sold) for a college textbook over the past three...
The quarterly sales data (number of copies sold) for a college textbook over the past three years follow. Quarter Year 1 Year 2 Year 3 1 1690 1800 1850 2 940 900 1100 3 2625 2900 2930 4 2500 2360 2615 a. Construct a time series plot. What type of pattern exists in the data? b. Show the four-quarter and centered moving average values for this time series. c. Compute the seasonal and adjusted seasonal indexes for the four quarters....
The quarterly sales data (number of copies sold) for a college textbook over the past three...
The quarterly sales data (number of copies sold) for a college textbook over the past three years follow. Click on the datafile logo to reference the data. quarter year 1 year 2 year 3   1 1690 1800 1850 2 940 900 1100 3 2625 2900 2930 4 2500    2360    2615 e. Deseasonalize the time series (to 3 decimals). Year Quarter Deseasonalized Value 1 1 2 3 4 2 1 2 3 4 3 1 2 3 4 f....
The quarterly sales (number of books sold) over the past 3 years are as shown below....
The quarterly sales (number of books sold) over the past 3 years are as shown below. Year Quarter Period Sales 1 1 1 1700 1 2 2 1000 1 3 3 2700 1 4 4 2500 2 1 5 1800 2 2 6 900 2 3 7 2900 2 4 8 2400 3 1 9 1800 3 2 10 1100 3 3 11 2900 3 4 12 2600 Construct a time series plot for this data. Paste the time series...
Suppose that the following are the quarterly sales data for the past 7 years. 1.Construct a...
Suppose that the following are the quarterly sales data for the past 7 years. 1.Construct a time series plot and develop linear trend equation using the original data (with seasonal components). 2.Calculate 4-quarter moving average values for this time series (column E). 3.Calculate centered moving average values and seasonal indexes (column F and G). 4.Calculate seasonal indexes (column J) for the four quarters. 5.Copy seasonal indexes (column J) to column O, and calculate deseasonalized number sold (column P). 6.Construct a...
Here are quarterly data for the past two years, from these data, prepare a forecast for...
Here are quarterly data for the past two years, from these data, prepare a forecast for the upcoming year using decompostion. foreccast years 9 to 12. FORECAST ERROR? Period Actual period Actual 1 300 5 416 2 540 6 760 3 885 7 1191 4 580 8 760
3.       Here are quarterly data for the past two years. From these data, prepare a forecast...
3.       Here are quarterly data for the past two years. From these data, prepare a forecast for the upcoming year using linear regression. Period Actual 1.00 300.00 2.00 540.00 3.00 885.00 4.00 580.00 5.00 416.00 6.00 760.00 7.00 1191.00 8.00 760.00 What are the forecasts for periods 9, 10, 11, and 12?
The number of loaves of bread sold per day by an organic bakery over the past...
The number of loaves of bread sold per day by an organic bakery over the past five years can be treated as a random variable that is normally distributed. This distribution has a mean of 77.5 and a standard deviation of 14.4 loaves. Suppose a random sample of 36 days has been selected. Determine the probability that the average number of loaves sold in the sample of days exceeds 80 loaves. First find the standard error of the mean. Now...
It appears that over the past 50 years, the number of farms in the United States...
It appears that over the past 50 years, the number of farms in the United States declined while the average size of farms increased. The following data provided by the U.S. Department of Agriculture show five-year interval data for U.S. farms. Use these data to develop the equation of a regression line to predict the average size of a farm (y) by the number of farms (x). Discuss the slope and y-intercept of the model. Year Number of Farms (millions)...
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT