do test only use techniqes found in files
roberto pulpo
ForecastingQUAN4630nov12.xlsxMov ave
| Data #1 | Data #2 | ||||||||||||
| Period | Actual | mov ave n=2 | Period | Actual | ma (2) | ma (4) | |||||||
| 1 | 120 | 1 | 99 | ||||||||||
| 2 | 130 | 2 | 164 | ||||||||||
| 3 | 128 | 125 | 3 | 578 | 131.5 | ||||||||
| 4 | 140 | 129 | 4 | 145 | 371 | ||||||||
| 5 | 155 | 134 | 5 | 127 | 361.5 | 246.5 | |||||||
| 6 | 160 | 147.5 | 6 | 163 | 136 | 253.5 | |||||||
| 7 | 170 | 157.5 | 7 | 660 | 145 | 253.25 | |||||||
| 8 | 165 | 165 | 8 | 200 | 411.5 | 273.75 | |||||||
| 9 | 150 | 167.5 | 9 | 108 | 430 | 287.5 | |||||||
| 10 | 145 | 157.5 | 10 | 142 | 154 | 282.75 | |||||||
| 11 | 147.5 | ||||||||||||
Actual 99 164 578 145 127 163 660 200 108 142 ma (2) 131.5 371 361.5 136 145 411.5 430 154 ma (4) 246.5 253.5 253.25 27 3.75 287.5 282.75
Exp smooth
| alpha | 0.1 | ||||
| Actual | smooth | smooth add-in | |||
| 1 | 120 | 120 | ERROR:#N/A | ||
| 2 | 130 | 120 | 120 | ||
| 3 | 128 | 121 | 121 | ||
| 4 | 140 | 121.7 | 121.7 | ||
| 5 | 155 | 123.53 | 123.53 | ||
| 6 | 160 | 126.677 | 126.677 | ||
| 7 | 170 | 130.0093 | 130.0093 | ||
| 8 | 165 | 134.00837 | 134.00837 | ||
| 9 | 150 | 137.107533 | 137.107533 | ||
| 10 | 145 | 138.3967797 | 138.3967797 | ||
| 139.05710173 | 139.05710173 | ||||
α is the smoothing factor (between 0 and 1) 1-α is the damping factor Exponential smoothing formula Jumpstart: Let first "smoothed" value be equal to the first actual value Smoothed forecast at period n = α(actual value at period n-1) + (1-α)(smoothed forecast at period n - 1) A larger alpha is more responsive to recent changes in data. A smaller alpha is less sensitive to changes and is therefore smoother
Holt Winters
| Month | Sales | holt winters | Period | Semester | Enrollment | holt winters | |||||||||||
| Jan-22 | 120 | 121.1025118192 | 1 | 1 | 5542 | 5782.2463644201 | |||||||||||
| Feb-22 | 130 | 131.1074960343 | 2 | 2 | 5186 | 5126.7559145757 | |||||||||||
| Mar-22 | 128 | 128.298659074 | 3 | 3 | 3512 | 3572.2004036131 | |||||||||||
| Apr-22 | 140 | 141.0823089511 | 4 | 1 | 5992 | 6047.6855694266 | |||||||||||
| May-22 | 155 | 154.4630261604 | 5 | 2 | 5277 | 5392.1951195822 | |||||||||||
| Jun-22 | 160 | 158.7567422086 | 6 | 3 | 3549 | 3837.6396086196 | |||||||||||
| Jul-22 | 170 | 168.7302901701 | 7 | 1 | 6011 | 6313.1247744331 | |||||||||||
| Aug-22 | 165 | 163.7138136263 | 8 | 2 | 5408 | 5657.6343245887 | |||||||||||
| Sep-22 | 150 | 147.6328554617 | 9 | 3 | 3937 | 4103.0788136261 | |||||||||||
| Oct-22 | 145 | 144.2584007935 | 10 | 1 | 6468 | 6578.5639794396 | |||||||||||
| Nov-22 | 155 | 152.6224171241 | 11 | 2 | 5543 | 5923.0735295952 | |||||||||||
| Dec-22 | 180 | 178.2558460492 | 12 | 3 | 4054 | 4368.5180186326 | |||||||||||
| Jan-23 | 135 | 133.6779101616 | 13 | 1 | 6857 | 6844.0031844461 | |||||||||||
| Feb-23 | 145 | 143.6828943768 | 14 | 2 | 6150 | 6188.5127346017 | |||||||||||
| Mar-23 | 142 | 140.8740574165 | 15 | 3 | 4634 | 4633.9572236391 | |||||||||||
| Apr-23 | 155 | 153.6577072935 | 16 | 7109.4423894525 | |||||||||||||
| May-23 | 168 | 167.0384245028 | 17 | 6453.9519396081 | |||||||||||||
| Jun-23 | 172 | 171.332140551 | 18 | 4899.3964286455 | |||||||||||||
| Jul-23 | 182 | 181.3056885125 | |||||||||||||||
| Aug-23 | 177 | 176.2892119687 | |||||||||||||||
| Sep-23 | 160 | 160.2082538041 | |||||||||||||||
| Oct-23 | 158 | 156.8337991359 | |||||||||||||||
| Nov-23 | 165 | 165.1978154665 | |||||||||||||||
| Dec-23 | 190 | 190.8312443916 | |||||||||||||||
| Jan-24 | 146.2533085041 | ||||||||||||||||
| Feb-24 | 156.2582927192 | ||||||||||||||||
| Mar-24 | 153.4494557589 | ||||||||||||||||
| Apr-24 | 166.2331056359 | ||||||||||||||||
| May-24 | 179.6138228453 | ||||||||||||||||
| Jun-24 | 183.9075388934 | ||||||||||||||||
| Jul-24 | 193.8810868549 | ||||||||||||||||
| Aug-24 | 188.8646103112 | ||||||||||||||||
| Sep-24 | 172.7836521465 | ||||||||||||||||
| Oct-24 | 169.4091974784 | ||||||||||||||||
| Nov-24 | 177.7732138089 | ||||||||||||||||
| Dec-24 | 203.4066427341 | ||||||||||||||||
| Jan-25 | 158.8287068465 |
Holt-Winters: An improvement on exponential smoothing that handles trends and seasonality well.
Sales 120 130 128 140 155 160 170 165 150 145 155 180 135 145 142 155 168 172 182 177 160 158 165 190 holt winters 121.10251181920509 131.10749603432365 128.29865907402885 141.08230895105066 154.46302616042109 158.75674220855487 168.7302901700759 163.71381362629683 147.63285546166804 144.25840079351747 152.62241712406615 178.25584604921585 133.6779 101616321 143.68289437675065 140.87405741645586 153.6577072934777 167.0384245028481 171.33214055098188 181.30568851250291 176.28921196872386 160.20825380409505 156.8337991359445 165.19781546649315 190.83124439164288 146.25330850405908 156.25829271917763 153.44945575888283 166.23310563590468 179.61382284527508 183.90753889340886 193.88108685492989 188.86461031115084 172.78365214652203 169.40919747837148 177.77321380892013 203.40664273406986 158.82870684648609
Enrollment 5542 5186 3512 5992 5277 3549 6011 5408 3937 6468 5543 4054 6857 6150 4634 holt winters 5782.2463644201489 5126.7559145757459 3572.2004036131375 6047.6855694266269 5392.1951195822239 3837.6396086196155 6313.1247744331049 5657.6343245887019 4103.0788136260935 6578.5639794395829 5923.0735295951799 4368.5180186325715 6844.00318444606 6188.5127346016579 4633.9572236390495 7109.442389452538 6453.9519396081359 4899.3964286455275
