Statistics Data analysis project
dalal_hg
Worksheet13ch16.1timeseriessolution_6849d57ff68cb2333279c51daad3c20a.docxWorksheet 13 ch 16.1
Analyzing and Forecasting Time-Series Data
16.7
a. The forecasting horizon is the lead time: the number of periods between when the forecast is made and time period to which it applies. Here the forecast is made in March and is applicable in September. There are six time periods (months) between March and September. Therefore, the forecasting horizon is 6 months.
b. The medium term forecast has a forecasting horizon of three months to two years. Since this forecasting horizon is six months, it would be considered to me a medium term forecast.
c. The forecasting period is the unit of time for which forecasts are to be made. Here that unit of time is a month.
d. The forecasting interval is the frequency with which new forecasts are prepared. Here a forecast is made each year (every 12 months). Therefore, the forecasting interval is 12months.
16.8
a.
|
Year |
Price |
Index |
|
1 |
320 |
100.0 |
|
2 |
334 |
104.4 |
|
3 |
329 |
102.8 |
|
4 |
344 |
107.5 |
|
5 |
358 |
111.9 |
|
6 |
347 |
108.4 |
|
7 |
383 |
119.7 |
|
8 |
404 |
126.3 |
|
9 |
397 |
124.1 |
|
10 |
411 |
128.4 |
b. The median selling price in year 10 has an index of 128.4. This means that the median selling price in year 10 is 28.4% above the median selling price in year 1.
c. The median selling price in year 5 has an index of 111.9. This means that the median selling price in year 5 is 11.9% above the median selling price in year one.
d. To determine the actual percentage increase, the calculation is
16.9.
a. This part of the exercise is done using Equation 16-1 following the steps shown in Example 16-1. Radio advertising has a base value of 300 and newspaper advertising has a base value of 400.
b. The unweighted aggregate index is found using Equation 16-2 following the steps shown in Example 16-2.
c. The Laspreyres Index is found using Equation 16-4 following Example 16-4.
|
. |
Radio |
% radio |
Newspaper |
Laspeyres |
|
1 |
300 |
0.3 |
400 |
100 |
|
2 |
310 |
0.42 |
420 |
104.59 |
|
3 |
330 |
0.42 |
460 |
113.78 |
|
4 |
346 |
0.4 |
520 |
126.43 |
|
5 |
362 |
0.38 |
580 |
139.08 |
|
6 |
380 |
0.37 |
640 |
151.89 |
|
7 |
496 |
0.43 |
660 |
165.08 |
a. The Paasche Index is constructed using Equation 16-3 following Example 16-3.
|
Year |
Radio |
% radio |
Newspaper |
Paasche |
|
1 |
300 |
0.3 |
400 |
100 |
|
2 |
310 |
0.42 |
420 |
104.41 |
|
3 |
330 |
0.42 |
460 |
113.22 |
|
4 |
346 |
0.4 |
520 |
124.77 |
|
5 |
362 |
0.38 |
580 |
136.33 |
|
6 |
380 |
0.37 |
640 |
148.12 |
|
7 |
496 |
0.43 |
660 |
165.12 |
4
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