The practice of creating a forecast that predicts the future need for a particular good or service
If demand planning is done correctly organisations can deliver excellent consumer services while meeting financial goals
Demand planning is considered to be a part of the supply chain management process which contributes towards the delivery of reliable goods and services that satisfy the needs of consumers
Forecasting
A prediction of demand that is based on statistical and mathematical analysis of past demand
Forecasting starts with predetermined assumptions based on experience, knowledge and judgement
Organisations require
SHORT TERM FORECAST: Are required for the scheduling of personnel, production and transportation
MEDIUM TERM FORECAST: Are required for the determination & scheduling of the future resource requirements in order to acquire raw materials, employ personnel or purchase equipment and machinery
LONG TERM FORECASTS: Are required for strategic planning. Decisions must take into account market opportunities, environment factors as well as internal resources
What to forecast
Is it for every product line, or for groups of products
Is it for every store or for stores grouped by province or only for total sales
Is it weekly data, monthly data or annual data
Organisations should consider
Time horizon
Frequency forecast
Efficiency and productivity of personnel
Forecastingtechniques
Qualitative
Quantitative
Quantitative forecasting
Uses mathematicalandstatistical methods duringforecastingprocess.Theinputfortheforecast is historicaldatawhich can be utilised to predict for the future
Time series
Quantitativeforecastingtechniquesthat use historicaldata to predictfuturevalues
Movingaverage
A forecastingmethodthatassumesthedemandforthegood or servicewillremainfairlyconstantover a period of time. It usesthemostrecentset of dataandmeasurestheaverageinformationwithin a specifictimeframe
Weightedmovingaverage
A forecastingmethod that gives moreweight to themostrecentdata, reducing the weight of datathatislessimportant
Exponentialsmoothing
A forecastingmethodthatrequires the most recentforecasts, actualdemand and thesmoothingconstantalpha. The newforecast will bebasedonthepreviouslyutilisedforecastandactualdemand
It is importantthatthere is notrend in the databefore the exponentialsmoothingforecasts, as the forecastsmay not beaccurate if there is atrend
The most recent forecast has the greatest weight in exponential smoothing and thereforeshould be the mostaccurate in predictingdemand, as opposed to themovingaveragesmethodwhere the weight for each period is fixed
Causal forecasting methods
Quantitative forecasting techniques that use independent variables to predict the dependent variable
Linearregression
A causalforecastingmethodthatexpressestheforecastedvariable as a linearfunction of an independentvariable
Multiple regression
A causal forecastingmethodthatallows for morethan one independentvariable to predictthedependentvariable
The developmentofsoftwarepackagesassistsorganisationswhencomputingregression and multipleregression
Qualitative forecasting
Forecastingbased on thejudgement of thoseinvolved, usingsoftdata and humanfactorsrather than mathematicaltechniques
Qualitativeforecastingmethods
Customersurveys
Jury ofexecutiveopinion
Salesforceopinion
Delphimethod
Forecasting process
1. Determine the purpose of the forecast
2. Identifythecorrecttimehorizon
3. Choosecorrecttechnique
4. Collectandanalysedata
5. Maketheforecast
6. Continuously monitortheforecast
Forecasting accuracy
Determined by evaluating the forecast against actual data, with a smaller variance indicating higher accuracy
Forecasting errors
Forecastingerror
Meanabsolutedeviation
Meansquareerror
Meanabsolute percentage error
Cloud-based forecasting
The use of cloud-basedsystemsforforecasting
Forecastingaccuracy
The accuracy of a forecast is determinedwhen it isevaluatedagainsttheactualdata,which are onlyderivedafter the forecasthas been established
An organisationmakesplansbased on its forecast, and thereforeaccuracycanbeonly be determinedafter a periodoftime
If the actual data are close to the forecasted data
Accuracy is high
Ifthere is asignificantvariancebetween the actualdataandtheforecasteddata
There is a lowlevelofaccuracy
Variancebetweentheactualdata and theforecasteddata
Reveals the relevance of the forecast
Whenthereisasmallervariance
The forecast is deemedto be relevant
Whenthere is significantvariance
The forecast isconsiderednot to be as relevant and is revisedaccordingly
Forecasting error
The difference between the actual quantity and the forecasts
Meanabsolutedeviation (MAD)
The sum of the absolute values of the individual forecasting errors divided by the number of periods
Mean squared error (MSE)
The average of the squared differences between the forecasted and observed values
Mean absolute percentage error (MAPE)
The absolute difference between the forecast and actual values, expressed as a percentage of actual value
Forecasting errors include mean absolute deviation, mean square error, and mean absolute percentage error
Cloud-based forecasting
The use of cloud computing technology to predict future events or trends over the internet