【正文】 h Edition, by William J. Stevenson Copyright 169。 31 McGrawHill/Irwin Operations Management, Seventh Edition, by William J. Stevenson Copyright 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting 簡(jiǎn)單預(yù)測(cè) 唉 , 給我點(diǎn)時(shí)間 .... 上周我們賣(mài)了 250輪胎.... 那么 , 下周我們應(yīng)該賣(mài) .... 314 McGrawHill/Irwin Operations Management, Seventh Edition, by William J. Stevenson Copyright 169。 20xx by PrenticeHall Inc Russell/Taylor Oper Mgt 3/e 季節(jié)性調(diào)節(jié)之例 需求 (1000件／季度 ) 年 1 2 3 4 總計(jì) 1995 1996 1997 總計(jì) Si 趨勢(shì)直線 y = + x 1998 (第 4年 )的預(yù)測(cè) = + (4) = 1998 1 1 42 0148 7 0 28S D D? ? ?? . . .SF1 = (S1) (F5) = ()() = SF2 = (S2) (F5) = ()() = SF3 = (S3) (F5) = ()() = SF4 = (S4) (F5) = ()() = 326 McGrawHill/Irwin Operations Management, Seventh Edition, by William J. Stevenson Copyright 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting MAD amp。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting 線性趨勢(shì)計(jì)算 y = + a = 812 (15) 5 = b = 5 (2499) 15(812) 5(55) 225 = 12495 12180 275 225 = 324 McGrawHill/Irwin Operations Management, Seventh Edition, by William J. Stevenson Copyright 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting Ch 10 7 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting ? 假定系統(tǒng)中存在因果關(guān)系 過(guò)去 == 未來(lái) ? 由于不確定性因素的存在使得預(yù)測(cè)很少準(zhǔn)確無(wú)誤 ? 對(duì)一組事物的預(yù)測(cè)比 對(duì)單個(gè)事物預(yù)測(cè)準(zhǔn)確 ? 當(dāng)預(yù)測(cè)時(shí)間跨度增加時(shí)， 預(yù)測(cè)精度將下降 我看這學(xué)期你 能得優(yōu)秀成績(jī)。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting Ch 10 15 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting Ch 10 38 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting Ch 10 39 169。 20xx by The McGrawHill Companies, Inc. All rights reserved. Forecasting 指數(shù)平滑法 ?假設(shè) —最近的觀測(cè)具有最高的預(yù)測(cè)價(jià)值 . – 因此在預(yù)測(cè)時(shí)，應(yīng)該給更近的數(shù)據(jù)賦予更高的權(quán)重 . Ft = Ft1 + ?(At1 Ft1) 319 McGrawHill/Irwin Operations Management, Seventh Edition, by