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    SAP AG 2002, Title of Presentation, Speaker Name / 3

    Overview of Forecasting in APO

    3

    33

    1

    11

    Univariate Forecast Basics

    2

    22 History

    4

    44 Univariate Models in APOModels in APOModels in APOModels in APO

    5

    55 Forecast Error Analysis

    6

    66

    7

    77

    Master Forecast Profile Setup

    Forecast Execution

    Overview of the Forecasting Workshop

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    SAP AG 2002, Title of Presentation, Speaker Name / 4

    333 Univariate Forecast Basics

    444 Univariate Models in APOModels in APOModels in APOModels in APO

    555 Forecast Error Analysis

    What we will talk about today

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    333 Univariate Forecast Basics

    444 Univariate Models in APOModels in APOModels in APOModels in APO

    555 Forecast Error Analysis

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    Elements of the Univariate Forecast

    Actual Value

    Basic Value

    Trend Value

    Seasonal Index

    Length of Season

    Initialization

    Ex-post Forecast

    Forecast

    Parameters

    Exceptions are models 13, 14, 35, 70, 80, 94

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    Actual Value

    DataValues

    Past Horizon

    Historical values used as the basis of theforecast

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    Basic Value

    DataValues

    Forecast Horizon

    Basic Value - Controls Vertical Placement

    1

    22000

    1000

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    Trend Value

    DataValues

    Forecast Horizon

    Trend - Slope of line

    1

    2.75

    -.75

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    Seasonal Index

    DataValues

    Forecast Horizon

    Seasonal index - Divergence from Basic Value

    1.00

    2.50

    .25

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    Length of Season

    DataValues

    Number of Periods in the SeasonTypically = one year

    Season

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    Initialization

    Basic value, Trend value, Seasonal indices, and the MeanAbsolute Deviation are initialized.

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    Ex-post Forecast

    An Ex post Forecast is a forecast run in the past for comparisonAn Ex post Forecast is a forecast run in the past for comparisonAn Ex post Forecast is a forecast run in the past for comparisonAn Ex post Forecast is a forecast run in the past for comparisonagainst historical values. The exagainst historical values. The exagainst historical values. The exagainst historical values. The ex----post forecast is used to measurepost forecast is used to measurepost forecast is used to measurepost forecast is used to measure

    model fit.model fit.model fit.model fit.

    Data

    Values

    Future

    Forecast

    History

    Initialization Ex-post Forecast

    History Values

    ForecastValues

    - Initialization length is dependent on the forecast model- Ex-post forecast length is the history horizon less the

    initialization horizon

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    Ex-post Forecast

    The following Models do not generate an ExThe following Models do not generate an ExThe following Models do not generate an ExThe following Models do not generate an Ex----post forecast:post forecast:post forecast:post forecast:

    Manual forecastManual forecastManual forecastManual forecast

    Historical data adoptedHistorical data adoptedHistorical data adoptedHistorical data adopted

    Weighted moving averageWeighted moving averageWeighted moving averageWeighted moving average

    Moving averageMoving averageMoving averageMoving average

    70707070

    60606060

    14141414

    13131313

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    General Calculation

    Basic(t), trend(t), seasonal(t)

    =

    Function(actual(t), basic(t-1), trend(t-1), seasonal(t-1s))

    Forecast = Function(basic(t), trend(t), seasonal(t))

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    Period 1 2 3 4 5 6 7 1 2 3 4

    History 80 95 100 115 125 110 110

    G - Basic Value 102 113

    T - Trend 10.0 10.3

    EX Ex-post 112 123

    F Forecast

    History Horizon Forecast Horizon

    Trend Model Example Calculate New Basic and Trend

    Trend Value T(t) = [ G(t) - G(t-1) ] + (1-)T(t-1)

    10.3 = .3 [ 113 102 ] + (.7) 10.0

    Basic Value G(t) = V(t) + (1-) [ G(t-1) + T(t-1) ]

    113 = .3 (115) + (.7) [ 102 + 10.0 ]

    Ex-Post Forecast Ex(t +i) = G(t) + i * T(t)Where i = 1

    123 = 113 + 10.3

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    Period 1 2 3 4 5 6 7 1 2 3 4

    History 80 95 100 115 125 110 110

    G - Basic Value 102 113

    T - Trend 10.0 10.3

    EX Ex-post 112 123

    F Forecast

    History Horizon Forecast Horizon

    Trend Model Example Calculation Repeated

    Ex-Post Forecast Ex(t +i) = G(t) + i * T(t)Where i = 1

    124 127

    10.5 8.3

    123 134 135

    124

    10.5

    123 134

    124 127 128

    10.5 8.3 6.1

    123 134 135

    134

    Forecast P(t+i) = G(t) + i * T(t)

    Basic Value G(t) = V(t) + (1-) [ G(t-1) + T(t-1) ]

    Trend Value T(t) = [ G(t) - G(t-1) ] + (1-)T(t-1)

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    Period 1 2 3 4 5 6 7 1 2 3 4

    History 80 95 100 115 125 110 110

    G - Basic Value 102 113 124 127 128 128

    T - Trend 10.0 10.3 10.5 8.3 6.1 6.1

    EX Ex-post 112 123 134 135

    F Forecast 134 140

    History Horizon Forecast Horizon

    Trend Model Example Calculation Repeated

    Ex-Post Forecast Ex(t +i) = G(t) + i * T(t)Where i = 1

    Forecast P(t+i) = G(t) + i * T(t)

    110

    128 128 128

    6.1 6.1 6.1

    135

    134 140 146

    1

    110

    128 128 128 128

    6.1 6.1 6.1 6.1

    135

    134 140 146 152

    2

    Basic Value G(t) = V(t) + (1-) [ G(t-1) + T(t-1) ]

    Trend Value T(t) = [ G(t) - G(t-1) ] + (1-)T(t-1)

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    Model parameters

    The model parameters, Alpha, Beta, and Gamma, control theweighting of each historical values.

    Alpha is used in the basic value calculation

    Beta is used in trend value calculation

    Gamma is used in the Seasonal index calculation

    The value for the parameters range from 0 to 1. A higher value will

    place more emphasis on recent history.

    The parameters also control how reactive the forecast is to changes inhistorical patterns.

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    SAP AG 2002, Title of Presentation, Speaker Name / 21

    333 Univariate Forecast Basics

    444 Univariate Models in APOModels in APOModels in APOModels in APO

    555 Forecast Error Analysis

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    Univariate Forecasting Models

    Constant ModelsConstant ModelsConstant ModelsConstant Models

    Moving Average ModelsMoving Average ModelsMoving Average ModelsMoving Average Models

    Trend ModelsTrend ModelsTrend ModelsTrend Models

    Seasonal ModelsSeasonal ModelsSeasonal ModelsSeasonal Models

    Seasonal Trend ModelsSeasonal Trend ModelsSeasonal Trend ModelsSeasonal Trend Models

    Automatic Model Selection I and IIAutomatic Model Selection I and IIAutomatic Model Selection I and IIAutomatic Model Selection I and II

    Sporadic DemandSporadic DemandSporadic DemandSporadic Demand

    Historical Data ModelHistorical Data ModelHistorical Data ModelHistorical Data Model

    Linear RegressionLinear RegressionLinear RegressionLinear Regression

    User ExitUser ExitUser ExitUser Exit

    C M d l

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    Constant Models

    3 models within the constant model group:3 models within the constant model group:3 models within the constant model group:3 models within the constant model group:

    Constant Model (10)Constant Model (10)Constant Model (10)Constant Model (10)

    1111stststst Order Exponential Smoothing (11)Order Exponential Smoothing (11)Order Exponential Smoothing (11)Order Exponential Smoothing (11)

    Constant Model with automatic Alpha adaptation (12)Constant Model with automatic Alpha adaptation (12)Constant Model with automatic Alpha adaptation (12)Constant Model with automatic Alpha adaptation (12)

    Constant Models follow the pattern:Constant Models follow the pattern:Constant Models follow the pattern:Constant Models follow the pattern:

    Same Formula !10 = 11

    C t t M d l 1st d E ti l S thi (10 11)

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    Constant Model 1st order Exponential Smoothing (10,11)

    Use this model when there are no seasonal variations or trendUse this model when there are no seasonal variations or trendUse this model when there are no seasonal variations or trendUse this model when there are no seasonal variations or trendpatterns. Alpha parameter controls the weighting of history inpatterns. Alpha parameter controls the weighting of history inpatterns. Alpha parameter controls the weighting of history inpatterns. Alpha parameter controls the weighting of history in

    determining the basic value.determining the basic value.determining the basic value.determining the basic value.

    Basic value and exBasic value and exBasic value and exBasic value and ex----post forecast are equalpost forecast are equalpost forecast are equalpost forecast are equal

    Higher alpha puts more weight on recent valuesHigher alpha puts more weight on recent valuesHigher alpha puts more weight on recent valuesHigher alpha puts more weight on recent values

    Higher alpha makes the forecast more reactive to recent changesHigher alpha makes the forecast more reactive to recent changesHigher alpha makes the forecast more reactive to recent changesHigher alpha makes the forecast more reactive to recent changes inininin

    historyhistoryhistoryhistory

    E l f C t t M d l

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    Example of a Constant Model

    Constant Model Automatic Adaptation of the Alpha factor

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    Co sta t ode uto at c daptat o o t e p a acto(12)

    The system automatically adjusts the alpha factor based on the iThe system automatically adjusts the alpha factor based on the iThe system automatically adjusts the alpha factor based on the iThe system automatically adjusts the alpha factor based on the initialnitialnitialnitialalpha and the smallest tracking signal.alpha and the smallest tracking signal.alpha and the smallest tracking signal.alpha and the smallest tracking signal.

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    Moving Average Formulas

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    Moving Average-Formulas

    Moving Average-13 Weighted Moving Average-14

    No ex-post forecast calculated

    Trend Models

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    Trend Models

    There are four models for data with trend:There are four models for data with trend:There are four models for data with trend:There are four models for data with trend:

    Forecast with Trend Model (20)Forecast with Trend Model (20)Forecast with Trend Model (20)Forecast with Trend Model (20)

    HoltHoltHoltHolts Method (21)s Method (21)s Method (21)s Method (21)

    Second Order Exponential Smoothing (22)Second Order Exponential Smoothing (22)Second Order Exponential Smoothing (22)Second Order Exponential Smoothing (22)

    Trend model with Automatic Alpha Adaptation (2nd order) (23)Trend model with Automatic Alpha Adaptation (2nd order) (23)Trend model with Automatic Alpha Adaptation (2nd order) (23)Trend model with Automatic Alpha Adaptation (2nd order) (23)

    Same Formula !20 = 21

    Holts Method (20 21)

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    Holt s Method (20, 21)

    Basic ValueBasic ValueBasic ValueBasic Value G(t) = V(t) + (1-) [ G(t-1) + T(t-1) ]

    Trend ValueTrend ValueTrend ValueTrend Value T(t) = [(G(t) - G(t-1) ] + (1-)T(t-1)

    Forecast value for period (t +1)Forecast value for period (t +1)Forecast value for period (t +1)Forecast value for period (t +1) P(t+i) = G(t) + i * T(t)

    Formulas

    Second Order Exponential Smoothing (22)

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    Second Order Exponential Smoothing (22)

    Encompasses a double smoothing method where the basic value ofEncompasses a double smoothing method where the basic value ofEncompasses a double smoothing method where the basic value ofEncompasses a double smoothing method where the basic value ofthe first calculation is used as the input for the second. Thethe first calculation is used as the input for the second. Thethe first calculation is used as the input for the second. Thethe first calculation is used as the input for the second. The result is aresult is aresult is aresult is a

    basic value that is more reactive to changes in demand whilebasic value that is more reactive to changes in demand whilebasic value that is more reactive to changes in demand whilebasic value that is more reactive to changes in demand while

    minimizing the trend effect.minimizing the trend effect.minimizing the trend effect.minimizing the trend effect.

    Trend with Automatic Alpha Adaptation (2nd order) (23)

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    Trend with Automatic Alpha Adaptation (2nd order) (23)

    This is the same as Second Order Exponential Smoothing except thThis is the same as Second Order Exponential Smoothing except thThis is the same as Second Order Exponential Smoothing except thThis is the same as Second Order Exponential Smoothing except theeeesystems determines the Alpha value. The minimum Alpha is 0.05 ansystems determines the Alpha value. The minimum Alpha is 0.05 ansystems determines the Alpha value. The minimum Alpha is 0.05 ansystems determines the Alpha value. The minimum Alpha is 0.05 andddd

    the maximum is 0.90. The system determines the Alpha factor thrthe maximum is 0.90. The system determines the Alpha factor thrthe maximum is 0.90. The system determines the Alpha factor thrthe maximum is 0.90. The system determines the Alpha factor throughoughoughough

    an iterative processes of comparing the MAD to the Error Total (an iterative processes of comparing the MAD to the Error Total (an iterative processes of comparing the MAD to the Error Total (an iterative processes of comparing the MAD to the Error Total (ET).ET).ET).ET).

    (Same Method as Constant with Automatic Alpha Adaptation).(Same Method as Constant with Automatic Alpha Adaptation).(Same Method as Constant with Automatic Alpha Adaptation).(Same Method as Constant with Automatic Alpha Adaptation).

    Trend Dampening Profile

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    Trend Dampening Profile

    As the historical values do not show a decrease in trend as theAs the historical values do not show a decrease in trend as theAs the historical values do not show a decrease in trend as theAs the historical values do not show a decrease in trend as the marketmarketmarketmarketmatures, a Trend Dampening profile can be used to smooth out thematures, a Trend Dampening profile can be used to smooth out thematures, a Trend Dampening profile can be used to smooth out thematures, a Trend Dampening profile can be used to smooth out the

    trend.trend.trend.trend.

    Seasonal Models

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    Seasonal Models

    Seasonal Models are used to depict a Seasonal forecast or a recuSeasonal Models are used to depict a Seasonal forecast or a recuSeasonal Models are used to depict a Seasonal forecast or a recuSeasonal Models are used to depict a Seasonal forecast or a recurringrringrringrringpattern, without any upwards or downwards slope. The pattern ocpattern, without any upwards or downwards slope. The pattern ocpattern, without any upwards or downwards slope. The pattern ocpattern, without any upwards or downwards slope. The pattern occurscurscurscurs

    across its season or a number of Seasonal Periods (Usuallyacross its season or a number of Seasonal Periods (Usuallyacross its season or a number of Seasonal Periods (Usuallyacross its season or a number of Seasonal Periods (Usually

    recommended to be 12 Months). The trend value and Beta in thisrecommended to be 12 Months). The trend value and Beta in thisrecommended to be 12 Months). The trend value and Beta in thisrecommended to be 12 Months). The trend value and Beta in this

    case are zero, signifying no upward or downward slope.case are zero, signifying no upward or downward slope.case are zero, signifying no upward or downward slope.case are zero, signifying no upward or downward slope.

    Seasonal Models

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    There are three Models associated with the seasonal patterns.There are three Models associated with the seasonal patterns.There are three Models associated with the seasonal patterns.There are three Models associated with the seasonal patterns.

    Forecast with the Seasonal Model (30)Forecast with the Seasonal Model (30)Forecast with the Seasonal Model (30)Forecast with the Seasonal Model (30)

    Seasonal Trend based on the WinterSeasonal Trend based on the WinterSeasonal Trend based on the WinterSeasonal Trend based on the Winters Method (31)s Method (31)s Method (31)s Method (31)

    Season + Linear Regression (35)Season + Linear Regression (35)Season + Linear Regression (35)Season + Linear Regression (35)

    Same Formula !30 = 31

    Forecast with the Seasonal Model (30)

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    ( )

    This model uses first order exponential smoothing where both AlpThis model uses first order exponential smoothing where both AlpThis model uses first order exponential smoothing where both AlpThis model uses first order exponential smoothing where both Alphahahahaand Gamma are assigned.and Gamma are assigned.and Gamma are assigned.and Gamma are assigned.

    Season + Linear Regression (35)

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    Seasonal indices calculated

    Seasonality removed from data

    Forecast created using linear regression

    Seasonality added back to forecast

    Seasonal Trend Models

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    There are two Models for the Seasonal Trend method:There are two Models for the Seasonal Trend method:There are two Models for the Seasonal Trend method:There are two Models for the Seasonal Trend method:

    Forecast with Seasonal Trend Model (40)Forecast with Seasonal Trend Model (40)Forecast with Seasonal Trend Model (40)Forecast with Seasonal Trend Model (40)

    First Order Exponential Smoothing (41)First Order Exponential Smoothing (41)First Order Exponential Smoothing (41)First Order Exponential Smoothing (41)

    Same Formula !40 = 41

    Also know as: Holt-Winters Method

    And Triple Exponential Smoothing

    First Order Exponential Smoothing (40, 41)

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    This Model encompasses the same Formula as 20,21,30,31 and usesThis Model encompasses the same Formula as 20,21,30,31 and usesThis Model encompasses the same Formula as 20,21,30,31 and usesThis Model encompasses the same Formula as 20,21,30,31 and usesassigned values for the Alpha, Beta and Gamma Coefficients.assigned values for the Alpha, Beta and Gamma Coefficients.assigned values for the Alpha, Beta and Gamma Coefficients.assigned values for the Alpha, Beta and Gamma Coefficients.

    Auto Selection Models

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    Auto Selection 1 (50)Auto Selection 1 (50)Auto Selection 1 (50)Auto Selection 1 (50)

    Test for Trend and Season (53)Test for Trend and Season (53)Test for Trend and Season (53)Test for Trend and Season (53)

    Test for Trend (51)Test for Trend (51)Test for Trend (51)Test for Trend (51)

    Test for Season (52)Test for Season (52)Test for Season (52)Test for Season (52)

    Seasonal model plus test for Trend (54)Seasonal model plus test for Trend (54)Seasonal model plus test for Trend (54)Seasonal model plus test for Trend (54)

    Trend Model plus test for Seasonal Pattern (55)Trend Model plus test for Seasonal Pattern (55)Trend Model plus test for Seasonal Pattern (55)Trend Model plus test for Seasonal Pattern (55)

    Auto Model Selection procedure 2 (56)Auto Model Selection procedure 2 (56)Auto Model Selection procedure 2 (56)Auto Model Selection procedure 2 (56)

    Same Formula !50 = 53

    Auto Selection 1 (50, 53)

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    Tests for Both Seasonal and Trend Patterns.Tests for Both Seasonal and Trend Patterns.Tests for Both Seasonal and Trend Patterns.Tests for Both Seasonal and Trend Patterns.Seasonal Test: The Auto Correlation Coefficient is Calculated, tSeasonal Test: The Auto Correlation Coefficient is Calculated, tSeasonal Test: The Auto Correlation Coefficient is Calculated, tSeasonal Test: The Auto Correlation Coefficient is Calculated, thehehehe

    Pattern is determined to be Seasonal if the Auto CorrelationPattern is determined to be Seasonal if the Auto CorrelationPattern is determined to be Seasonal if the Auto CorrelationPattern is determined to be Seasonal if the Auto Correlation

    Coefficient is Greater than 0.3.Coefficient is Greater than 0.3.Coefficient is Greater than 0.3.Coefficient is Greater than 0.3.

    Auto Selection 1 (50, 53)

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    A Trend Significance test is carried outA Trend Significance test is carried outA Trend Significance test is carried outA Trend Significance test is carried out

    If both are determined to be significant, a Seasonal Trend ModelIf both are determined to be significant, a Seasonal Trend ModelIf both are determined to be significant, a Seasonal Trend ModelIf both are determined to be significant, a Seasonal Trend Model isisisis

    used.used.used.used.

    If neither tests is determined to be Significant, then the ConstIf neither tests is determined to be Significant, then the ConstIf neither tests is determined to be Significant, then the ConstIf neither tests is determined to be Significant, then the Constantantantant

    Model is chosen as a defaultModel is chosen as a defaultModel is chosen as a defaultModel is chosen as a default

    Test for Trend (51)

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    Used to Test only for Trend.Used to Test only for Trend.Used to Test only for Trend.Used to Test only for Trend.

    This follows the Trend Significance test previously defined. IfThis follows the Trend Significance test previously defined. IfThis follows the Trend Significance test previously defined. IfThis follows the Trend Significance test previously defined. If nononono

    Significance is found then a Constant Model is Chosen.Significance is found then a Constant Model is Chosen.Significance is found then a Constant Model is Chosen.Significance is found then a Constant Model is Chosen.

    Test for Season (52)

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    Used to Test only for Seasonal Pattern.Used to Test only for Seasonal Pattern.Used to Test only for Seasonal Pattern.Used to Test only for Seasonal Pattern.

    This follows theThis follows theThis follows theThis follows the AutoCorrelationAutoCorrelationAutoCorrelationAutoCorrelation Coefficient Test andCoefficient Test andCoefficient Test andCoefficient Test and choseschoseschoseschoses thethethethe

    Seasonal Model if the value is above 0.3. If not a Constant ModSeasonal Model if the value is above 0.3. If not a Constant ModSeasonal Model if the value is above 0.3. If not a Constant ModSeasonal Model if the value is above 0.3. If not a Constant Model isel isel isel is

    chosen.chosen.chosen.chosen.

    Seasonal model plus test for Trend (54)

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    Assumes Seasonal pattern exists and tests for Trend pattern. IfAssumes Seasonal pattern exists and tests for Trend pattern. IfAssumes Seasonal pattern exists and tests for Trend pattern. IfAssumes Seasonal pattern exists and tests for Trend pattern. If aaaa

    trend significance is found, then a Seasonal Trend Model is usedtrend significance is found, then a Seasonal Trend Model is usedtrend significance is found, then a Seasonal Trend Model is usedtrend significance is found, then a Seasonal Trend Model is used. If. If. If. If

    no significance is found than a Seasonal Model is used.no significance is found than a Seasonal Model is used.no significance is found than a Seasonal Model is used.no significance is found than a Seasonal Model is used.

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    Summary of the Automodel 1 selection process

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    This shows the Model chosen under the following Conditions:This shows the Model chosen under the following Conditions:This shows the Model chosen under the following Conditions:This shows the Model chosen under the following Conditions:

    Automodel If:Trend If: Season Then:Uses Model

    40 - Seasonal Trend

    20 - Trend

    Yes

    No

    Yes byDefault

    55 - Trend Model plus testfor Season

    30 - Season

    40 - Seasonal Trend

    Yes by

    Default

    No

    Yes

    54 - Seasonal Model plus

    test for Trend

    30 - Season

    10 - Constant

    Yes

    No

    N/A52 - Test for Season

    30 - Trend

    10 - Constant

    N/AYes

    No

    51 - Test for Trend

    10 - Constant

    20 - Trend

    30 - Season

    40 - Seasonal Trend

    No

    No

    Yes

    Yes

    No

    Yes

    No

    Yes

    50 - Auto Selection 1

    or

    53 - Test for Trend andSeason

    Auto Model Selection procedure 2 (56)

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    Tests for Constant, Seasonal and/or Trend models while attemptinTests for Constant, Seasonal and/or Trend models while attemptinTests for Constant, Seasonal and/or Trend models while attemptinTests for Constant, Seasonal and/or Trend models while attempting tog tog tog to

    minimize Error by adjusting Alpha, Beta and Gamma..minimize Error by adjusting Alpha, Beta and Gamma..minimize Error by adjusting Alpha, Beta and Gamma..minimize Error by adjusting Alpha, Beta and Gamma..

    This model adjusts Alpha, Beta and Gamma between the values of 0This model adjusts Alpha, Beta and Gamma between the values of 0This model adjusts Alpha, Beta and Gamma between the values of 0This model adjusts Alpha, Beta and Gamma between the values of 0.1.1.1.1

    to 0.5 in 0.1 increments while calculating the Mean Absolute Devto 0.5 in 0.1 increments while calculating the Mean Absolute Devto 0.5 in 0.1 increments while calculating the Mean Absolute Devto 0.5 in 0.1 increments while calculating the Mean Absolute Deviationiationiationiation

    (MAD) for each Iteration. The iteration with the Lowest MAD is(MAD) for each Iteration. The iteration with the Lowest MAD is(MAD) for each Iteration. The iteration with the Lowest MAD is(MAD) for each Iteration. The iteration with the Lowest MAD is thethethetheModel chosen with the appropriate smoothing factors.Model chosen with the appropriate smoothing factors.Model chosen with the appropriate smoothing factors.Model chosen with the appropriate smoothing factors.

    Comparision between 50 and 56 (Auto model 1 & 2)

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    Auto Selection Model 1 Auto Selection Model 2Auto Selection Model 1 Auto Selection Model 2Auto Selection Model 1 Auto Selection Model 2Auto Selection Model 1 Auto Selection Model 2

    Chooses Best Fit of Constant, Trend,Chooses Best Fit of Constant, Trend,Chooses Best Fit of Constant, Trend,Chooses Best Fit of Constant, Trend,

    Seasonal, Seasonal Trend.Seasonal, Seasonal Trend.Seasonal, Seasonal Trend.Seasonal, Seasonal Trend.

    If no Pattern Detected defaults ConstantIf no Pattern Detected defaults ConstantIf no Pattern Detected defaults ConstantIf no Pattern Detected defaults Constant

    ModelModelModelModel

    Resource Intensive (NotResource Intensive (NotResource Intensive (NotResource Intensive (Not

    recommended for Production use)recommended for Production use)recommended for Production use)recommended for Production use)

    Not as precise as Auto Model 2Not as precise as Auto Model 2Not as precise as Auto Model 2Not as precise as Auto Model 2

    Determines Best Fit through throughDetermines Best Fit through throughDetermines Best Fit through throughDetermines Best Fit through through

    Iterative approach of adjustingIterative approach of adjustingIterative approach of adjustingIterative approach of adjusting

    smoothing factors (Alpha, Beta,smoothing factors (Alpha, Beta,smoothing factors (Alpha, Beta,smoothing factors (Alpha, Beta,

    Gamma) and determining SmallestGamma) and determining SmallestGamma) and determining SmallestGamma) and determining SmallestMean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)

    Determines Seasonal and TrendDetermines Seasonal and TrendDetermines Seasonal and TrendDetermines Seasonal and Trend

    Significance through Formulas forSignificance through Formulas forSignificance through Formulas forSignificance through Formulas for

    Auto Correlation (SeasonalAuto Correlation (SeasonalAuto Correlation (SeasonalAuto Correlation (Seasonal

    Significance) and TrendSignificance) and TrendSignificance) and TrendSignificance) and TrendSignificance TestsSignificance TestsSignificance TestsSignificance Tests

    The Croston Model (80)

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    The Croston Model (80) is used when demand is sporadic orThe Croston Model (80) is used when demand is sporadic orThe Croston Model (80) is used when demand is sporadic orThe Croston Model (80) is used when demand is sporadic or

    intermittent. The return is a Constant model to meet the possibintermittent. The return is a Constant model to meet the possibintermittent. The return is a Constant model to meet the possibintermittent. The return is a Constant model to meet the possiblelelele

    sporadic demand.sporadic demand.sporadic demand.sporadic demand.

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    Manual Forecast (70)

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    The Manual Forecast (70) allows the planner to set their own valThe Manual Forecast (70) allows the planner to set their own valThe Manual Forecast (70) allows the planner to set their own valThe Manual Forecast (70) allows the planner to set their own values toues toues toues to

    generate a forecast. The values chosen are all the values thatgenerate a forecast. The values chosen are all the values thatgenerate a forecast. The values chosen are all the values thatgenerate a forecast. The values chosen are all the values that makemakemakemake

    up the forecast these are the Smoothing coefficients Alpha, Betup the forecast these are the Smoothing coefficients Alpha, Betup the forecast these are the Smoothing coefficients Alpha, Betup the forecast these are the Smoothing coefficients Alpha, Beta,a,a,a,

    Gamma (from the Profile) and the Basic, Trend value and SeasonGamma (from the Profile) and the Basic, Trend value and SeasonGamma (from the Profile) and the Basic, Trend value and SeasonGamma (from the Profile) and the Basic, Trend value and Seasonalalalal

    Index. This model should not be used for Background Processing.Index. This model should not be used for Background Processing.Index. This model should not be used for Background Processing.Index. This model should not be used for Background Processing.

    No Forecast (98)

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    No forecast is conductedNo forecast is conductedNo forecast is conductedNo forecast is conducted

    External Forecast (99)

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    It is also possible to define your own Forecasting model if theIt is also possible to define your own Forecasting model if theIt is also possible to define your own Forecasting model if theIt is also possible to define your own Forecasting model if the modelmodelmodelmodel

    you commonly use is not provided. The external Forecasting featyou commonly use is not provided. The external Forecasting featyou commonly use is not provided. The external Forecasting featyou commonly use is not provided. The external Forecasting featureureureure

    allows you to use ABAP to code your own forecasting modelallows you to use ABAP to code your own forecasting modelallows you to use ABAP to code your own forecasting modelallows you to use ABAP to code your own forecasting model.

    Trend, Seasonal, Seasonal Trend overview: Formula

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    Explanation of the Variables

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    333 Univariate Forecast Basics

    444 Univariate Models in APOModels in APOModels in APOModels in APO

    555 Forecast Error Analysis

    Forecast Accuracy Measurements

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    Mean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)Mean Absolute Deviation (MAD)

    Error Total (ET)Error Total (ET)Error Total (ET)Error Total (ET)

    Mean Absolute Percentage Error (MAPE)Mean Absolute Percentage Error (MAPE)Mean Absolute Percentage Error (MAPE)Mean Absolute Percentage Error (MAPE)

    Mean Square Error (MSE)Mean Square Error (MSE)Mean Square Error (MSE)Mean Square Error (MSE)

    Square Root of the Mean Squared Error (RMSE)Square Root of the Mean Squared Error (RMSE)Square Root of the Mean Squared Error (RMSE)Square Root of the Mean Squared Error (RMSE)

    Mean Percentage Error (MPE)Mean Percentage Error (MPE)Mean Percentage Error (MPE)Mean Percentage Error (MPE)

    Mean Absolute Deviation (MAD)

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    The Mean Absolute Deviation is calculated by the absolute differThe Mean Absolute Deviation is calculated by the absolute differThe Mean Absolute Deviation is calculated by the absolute differThe Mean Absolute Deviation is calculated by the absolute differenceenceenceence

    between the exbetween the exbetween the exbetween the ex----post forecast and the actual value.post forecast and the actual value.post forecast and the actual value.post forecast and the actual value.

    The Mean Absolute Deviation is the error calculation used toThe Mean Absolute Deviation is the error calculation used toThe Mean Absolute Deviation is the error calculation used toThe Mean Absolute Deviation is the error calculation used to

    determine the best fit in the Auto Model 2 Forecasting Model.determine the best fit in the Auto Model 2 Forecasting Model.determine the best fit in the Auto Model 2 Forecasting Model.determine the best fit in the Auto Model 2 Forecasting Model.

    Error Total (ET)

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    The Error Total is the sum of the difference between the ActualThe Error Total is the sum of the difference between the ActualThe Error Total is the sum of the difference between the ActualThe Error Total is the sum of the difference between the Actual andandandand

    the Exthe Exthe Exthe Ex----post forecast.post forecast.post forecast.post forecast.

    Mean Square Error (MSE)

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    The Mean Square Error is the Average of the sum of the square ofThe Mean Square Error is the Average of the sum of the square ofThe Mean Square Error is the Average of the sum of the square ofThe Mean Square Error is the Average of the sum of the square of

    each difference between the exeach difference between the exeach difference between the exeach difference between the ex----post forecast and the Actual value.post forecast and the Actual value.post forecast and the Actual value.post forecast and the Actual value.

    Mean Absolute Percentage Error (MAPE)

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    The Mean Absolute Percentage Error is the Average Absolute PerceThe Mean Absolute Percentage Error is the Average Absolute PerceThe Mean Absolute Percentage Error is the Average Absolute PerceThe Mean Absolute Percentage Error is the Average Absolute Percentntntnt

    Error between the Actual Values and their corresponding ExError between the Actual Values and their corresponding ExError between the Actual Values and their corresponding ExError between the Actual Values and their corresponding Ex----postpostpostpost

    Forecast Values.Forecast Values.Forecast Values.Forecast Values.

    Root mean Square Error (RMSE)

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    The Root Mean Square Error is the Square root of the average ofThe Root Mean Square Error is the Square root of the average ofThe Root Mean Square Error is the Square root of the average ofThe Root Mean Square Error is the Square root of the average of thethethethe

    sum of the squared difference between the Actual and Exsum of the squared difference between the Actual and Exsum of the squared difference between the Actual and Exsum of the squared difference between the Actual and Ex----postpostpostpost

    Forecast value.Forecast value.Forecast value.Forecast value.

    Mean Percentage Error (MPE)Mean Percentage Error (MPE)Mean Percentage Error (MPE)Mean Percentage Error (MPE)

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    The Mean Percentage Error is the average percentage error of theThe Mean Percentage Error is the average percentage error of theThe Mean Percentage Error is the average percentage error of theThe Mean Percentage Error is the average percentage error of the

    difference between the Exdifference between the Exdifference between the Exdifference between the Ex----post Forecast and the Actual values.post Forecast and the Actual values.post Forecast and the Actual values.post Forecast and the Actual values.

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    Thank You