/// <summary>
/// Predict samples using saved model.
/// </summary>
/// <param name="mlContext">ML.NET context.</param>
/// <param name="lastMonthProductData">The last month of product data in the monthly data series.</param>
/// <param name="outputModelPath">Model file path</param>
private static void TestPrediction(MLContext mlContext, ProductData lastMonthProductData, string outputModelPath)
{
ConsoleWriteHeader("Testing product unit sales forecast Time Series model");
// Load the forecast engine that has been previously saved.
ITransformer forecaster;
using (var file = File.OpenRead(outputModelPath))
{
forecaster = mlContext.Model.Load(file, out DataViewSchema schema);
}
// We must create a new prediction engine from the persisted model.
TimeSeriesPredictionEngine <ProductData, ProductUnitTimeSeriesPrediction> forecastEngine = forecaster.CreateTimeSeriesEngine <ProductData, ProductUnitTimeSeriesPrediction>(mlContext);
// Get the prediction; this will include the forecasted product units sold for the next 2 months since this the time period specified in the `horizon` parameter when the forecast estimator was originally created.
Console.WriteLine("\n** Original prediction **");
ProductUnitTimeSeriesPrediction originalSalesPrediction = forecastEngine.Predict();
// Compare the units of the first forecasted month to the actual units sold for the next month.
var predictionMonth = lastMonthProductData.month == 12 ? 1 : lastMonthProductData.month + 1;
var predictionYear = predictionMonth < lastMonthProductData.month ? lastMonthProductData.year + 1 : lastMonthProductData.year;
Console.WriteLine($"Product: {lastMonthProductData.productId}, Month: {predictionMonth}, Year: {predictionYear} " +
$"- Real Value (units): {lastMonthProductData.next}, Forecasted (units): {originalSalesPrediction.ForecastedProductUnits[0]}");
// Get the first forecasted month's confidence interval bounds.
Console.WriteLine($"Confidence interval: [{originalSalesPrediction.ConfidenceLowerBound[0]} - {originalSalesPrediction.ConfidenceUpperBound[0]}]\n");
// Get the units of the second forecasted month.
Console.WriteLine($"Product: {lastMonthProductData.productId}, Month: {lastMonthProductData.month + 2}, Year: {lastMonthProductData.year}, " +
$"Forecasted (units): {originalSalesPrediction.ForecastedProductUnits[1]}");
// Get the second forecasted month's confidence interval bounds.
Console.WriteLine($"Confidence interval: [{originalSalesPrediction.ConfidenceLowerBound[1]} - {originalSalesPrediction.ConfidenceUpperBound[1]}]\n");
// Update the forecasting model with the next month's actual product data to get an updated prediction; this time, only forecast product sales for 1 month ahead.
Console.WriteLine("** Updated prediction **");
ProductData newProductData = SampleProductData.MonthlyData.Where(p => p.productId == lastMonthProductData.productId).Single();
ProductUnitTimeSeriesPrediction updatedSalesPrediction = forecastEngine.Predict(newProductData, horizon: 1);
// Save the updated forecasting model.
forecastEngine.CheckPoint(mlContext, outputModelPath);
// Get the units of the updated forecast.
predictionMonth = lastMonthProductData.month >= 11 ? (lastMonthProductData.month + 2) % 12 : lastMonthProductData.month + 2;
predictionYear = predictionMonth < lastMonthProductData.month ? lastMonthProductData.year + 1 : lastMonthProductData.year;
Console.WriteLine($"Product: {lastMonthProductData.productId}, Month: {predictionMonth}, Year: {predictionYear}, " +
$"Forecasted (units): {updatedSalesPrediction.ForecastedProductUnits[0]}");
// Get the updated forecast's confidence interval bounds.
Console.WriteLine($"Confidence interval: [{updatedSalesPrediction.ConfidenceLowerBound[0]} - {updatedSalesPrediction.ConfidenceUpperBound[0]}]\n");
}
static void Forecast(IDataView data, int horizon, TimeSeriesPredictionEngine <InputModel, OutputModel> forecaster, MLContext context)
{
var originalData = context.Data.CreateEnumerable <InputModel>(data, false);
var forecast = forecaster.Predict();
var forecastOutput = context
.Data
.CreateEnumerable <InputModel>(data, false)
.Take(horizon)
.Select((InputModel sell, int index) =>
{
var pastYearsSells = originalData.Where(item => item.SellMonth.Equals(index + 1)).OrderBy(item => item.SellYear);
var stringfiedPastYearsSells = pastYearsSells.Select(item => $"\t{item.SellYear} sells: {item.Value}\n");
var month = sell.SellMonth;
float actualSells = sell.Value;
float lowerEstimate = Math.Max(0, forecast.LowerBoundSells[index]);
float estimate = forecast.ForecastedSells[index];
float upperEstimate = forecast.UpperBoundSells[index];
return($"Month: {month}\n" +
$"Other Year Sells:\n{string.Concat(stringfiedPastYearsSells)}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}\n");
});
foreach (var item in forecastOutput)
{
Console.WriteLine(item);
}
}
public async Task <IActionResult> GetProductUnitDemandEstimation(string productId)
{
// Get product history.
var productHistory = await _queries.GetProductDataAsync(productId);
// Supplement the history with synthetic data.
var supplementedProductHistory = TimeSeriesDataGenerator.SupplementData(mlContext, productHistory);
var supplementedProductHistoryLength = supplementedProductHistory.Count(); // 36
var supplementedProductDataView = mlContext.Data.LoadFromEnumerable(supplementedProductHistory);
// Create and add the forecast estimator to the pipeline.
IEstimator <ITransformer> forecastEstimator = mlContext.Forecasting.ForecastBySsa(
outputColumnName: nameof(ProductUnitTimeSeriesPrediction.ForecastedProductUnits),
inputColumnName: nameof(ProductData.units), // This is the column being forecasted.
windowSize: 12, // Window size is set to the time period represented in the product data cycle; our product cycle is based on 12 months, so this is set to a factor of 12, e.g. 3.
seriesLength: supplementedProductHistoryLength, // TODO: Need clarification on what this should be set to; assuming product series length for now.
trainSize: supplementedProductHistoryLength, // TODO: Need clarification on what this should be set to; assuming product series length for now.
horizon: 1, // Indicates the number of values to forecast; 1 indicates that the next month of product units will be forecasted.
confidenceLevel: 0.95f, // TODO: Is this the same as prediction interval, where this indicates that we are 95% confidence that the forecasted value will fall within the interval range?
confidenceLowerBoundColumn: nameof(ProductUnitTimeSeriesPrediction.ConfidenceLowerBound), // TODO: See above comment.
confidenceUpperBoundColumn: nameof(ProductUnitTimeSeriesPrediction.ConfidenceUpperBound)); // TODO: See above comment.
// Train the forecasting model for the specified product's data series.
ITransformer forecastTransformer = forecastEstimator.Fit(supplementedProductDataView);
// Create the forecast engine used for creating predictions.
TimeSeriesPredictionEngine <ProductData, ProductUnitTimeSeriesPrediction> forecastEngine = forecastTransformer.CreateTimeSeriesEngine <ProductData, ProductUnitTimeSeriesPrediction>(mlContext);
// Predict.
var nextMonthUnitDemandEstimation = forecastEngine.Predict();
return(Ok(nextMonthUnitDemandEstimation.ForecastedProductUnits.First()));
}
static void Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict();
IEnumerable <string> forecastOutput =
mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput sale, int index) =>
{
string SaleDate = sale.SalesDate.ToShortDateString();
float actualSale = sale.TotalSales;
float lowerEstimate = Math.Max(0, forecast.LowerBoundSales[index]);
float estimate = forecast.ForecastedSales[index];
float upperEstimate = forecast.UpperBoundSales[index];
return($"Date: {SaleDate}\n" +
$"Actual Rentals: {actualSale}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}\n");
});
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
}
public async Task <IActionResult> GetProductUnitDemandEstimation(string productId)
{
// Get product history for the selected product
var productHistory = await _queries.GetProductDataAsync(productId);
var productDataView = mlContext.Data.LoadFromEnumerable(productHistory);
// Create and add the forecast estimator to the pipeline.
IEstimator <ITransformer> forecastEstimator = mlContext.Forecasting.ForecastBySsa(
outputColumnName: nameof(ProductUnitTimeSeriesPrediction.ForecastedProductUnits),
inputColumnName: nameof(ProductData.units), // This is the column being forecasted.
windowSize: 12, // Window size is set to the time period represented in the product data cycle; our product cycle is based on 12 months, so this is set to a factor of 12, e.g. 3.
seriesLength: productHistory.Count(), // This parameter specifies the number of data points that are used when performing a forecast.
trainSize: productHistory.Count(), // This parameter specifies the total number of data points in the input time series, starting from the beginning.
horizon: 1, // Indicates the number of values to forecast; 1 indicates that the next month of product units will be forecasted.
confidenceLevel: 0.95f, // Indicates the likelihood the real observed value will fall within the specified interval bounds.
confidenceLowerBoundColumn: nameof(ProductUnitTimeSeriesPrediction.ConfidenceLowerBound), //This is the name of the column that will be used to store the lower interval bound for each forecasted value.
confidenceUpperBoundColumn: nameof(ProductUnitTimeSeriesPrediction.ConfidenceUpperBound)); //This is the name of the column that will be used to store the upper interval bound for each forecasted value.
// Train the forecasting model for the specified product's data series.
ITransformer forecastTransformer = forecastEstimator.Fit(productDataView);
// Create the forecast engine used for creating predictions.
TimeSeriesPredictionEngine <ProductData, ProductUnitTimeSeriesPrediction> forecastEngine = forecastTransformer.CreateTimeSeriesEngine <ProductData, ProductUnitTimeSeriesPrediction>(mlContext);
// Predict.
var nextMonthUnitDemandEstimation = forecastEngine.Predict();
return(Ok(nextMonthUnitDemandEstimation.ForecastedProductUnits.First()));
}
/// <summary>
/// Применение модели для прогнозирования спроса
/// </summary>
/// <param name="testData"></param>
/// <param name="horizon"></param>
/// <param name="forecaster"></param>
/// <param name="mlContext"></param>
static void Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict();
//Сравните фактические и прогнозируемые значения по семи периодам.
IEnumerable <string> forecastOutput = mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput rental, int index) =>
{
string rentalDate = rental.RentalDate.ToShortDateString();
float actualRentals = rental.TotalRentals;
float lowerEstimate = Math.Max(0, forecast.LowerBoundRentals[index]);
float estimate = forecast.ForecastedRentals[index];
float upperEstimate = forecast.UpperBoundRentals[index];
return($"Date: {rentalDate}\n" +
$"Actual Rentals: {actualRentals}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}\n");
});
Console.WriteLine("Rental Forecast");
Console.WriteLine("---------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
}
static void Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict();
IEnumerable <string> forecastOutput = mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput passants, int index) =>
{
//string jour = Enum.GetName(typeof(DayOfWeek), passants.Jour);
float semaine = passants.Semaine;
float jour = passants.Jour;
//DateTime horaire = passants.Horaire;
float actualPassants = passants.NbPassants;
float lowerEstimate = Math.Max(0, forecast.LowerBoundPassants[index]);
float estimate = forecast.ForecastedPassants[index];
float upperEstimate = forecast.UpperBoundPassants[index];
return($"Date: {jour}\n" +
$"Actual Passants: {actualPassants}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}\n");
});
Console.WriteLine("Passants Forecast");
Console.WriteLine("---------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
}
public void Forecast(IDataView compareAgainst, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict(horizon);
IEnumerable <string> forecastOutput =
mlContext.Data.CreateEnumerable <ModelInput>(compareAgainst, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput input, int index) =>
{
string purchaseDate = input.Date.ToString("yyyy-MM-dd");
float actualSales = input.TotalSold;
float lowerEstimate = Math.Max(0, forecast.LowerBoundTotalSold[index]);
float estimate = forecast.ForecastedTotalSold[index];
float upperEstimate = forecast.UpperBoundTotalSold[index];
return($"Date: {purchaseDate}\n" +
$"Actual Sales: {actualSales}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}\n");
});
Console.WriteLine("Purchase Forecast");
Console.WriteLine("---------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
}
static List <ModelOutputExt> Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict();
List <ModelOutputExt> moextList = new List <ModelOutputExt>();
IEnumerable <ModelOutputExt> forecastOutput =
mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput sale, int index) =>
{
ModelOutputExt mext = new ModelOutputExt();
mext.ForecastedSales = (float)(Math.Max(0, Math.Round(forecast.ForecastedSales[index], 0)));
mext.LowerBoundSales = Math.Max(0, forecast.LowerBoundSales[index]);
mext.UpperBoundSales = forecast.UpperBoundSales[index];
mext.SalesDate = sale.SalesDate.ToShortDateString();
mext.TotalSales = sale.TotalSales;
mext.indexX = index;
return(mext);
});
foreach (var prediction in forecastOutput)
{
moextList.Add(prediction);
}
return(moextList);
}
static void Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext)
{
ModelOutput forecast = forecaster.Predict();
int i = 0;
IEnumerable <string> forecastOutput =
mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput rental, int index) =>
{
i++;
string Date = rental.Invoice_Date.ToShortDateString();
float actualDays = rental.OverDue_Days;
float lowerEstimate = Math.Max(0, forecast.MinimumDays[index]);
float estimate = forecast.ForecastedDays[index];
float upperEstimate = forecast.MaximumDays[index];
return
// $"No : {i}\n" +
($"Date : {Date}\n" +
$"Actual Days : {actualDays}\n" +
$"Lower Estimate Days : {lowerEstimate}\n" +
$"Forecast Days : {estimate}\n" +
$"Upper Estimate Days : {upperEstimate}\n");
});
// Output predictions
Console.WriteLine("Rental Forecast");
Console.WriteLine("---------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
}
private static void Forecast(IDataView testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster)
{
var forecast = forecaster.Predict();
// Align actual & forecast values for seven periods
var forecastOutput = _mlContext.Data.CreateEnumerable <ModelInput>(testData, reuseRowObject: false)
.Take(horizon)
.Select((ModelInput rental, int index) =>
{
string rentalDate = rental.RentalDate.ToShortDateString();
float actualRentals = rental.TotalRentals;
float lowerEstimate = Math.Max(0, forecast.LowerBoundRentals[index]);
float estimate = forecast.ForecastedRentals[index];
float upperEstimate = forecast.UpperBoundRentals[index];
return($"Date: {rentalDate}\n" +
$"Actual Rentals: {actualRentals}\n" +
$"Lower Estimate: {lowerEstimate}\n" +
$"Forecast: {estimate}\n" +
$"Upper Estimate: {upperEstimate}");
});
Console.WriteLine("Rental Forecast");
Console.WriteLine("--------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
Console.WriteLine("");
}
}
static void Main(string[] args)
{
var mlContext = new MLContext();
int c = 0;
float predictedPrice = 0;
while (c < 10)
{
IEnumerable <BTC_TimeSeries> data = GetTrainingData(mlContext);
IDataView trainingData = mlContext.Data.LoadFromEnumerable <BTC_TimeSeries>(data);
var offset = TimeSpan.FromSeconds(data.Last().TimeStamp);
var epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
DateTime lastTime = epoch.Add(offset).ToLocalTime();
int seriesLength = data.Count();
var estimator = mlContext.Forecasting.ForecastBySsa(outputColumnName: nameof(PredictedSeries.ForecastedPrice),
inputColumnName: nameof(BTC_TimeSeries.Price),
windowSize: 360,
seriesLength: seriesLength,
trainSize: seriesLength,
horizon: 5,
confidenceLevel: 0.95f,
confidenceLowerBoundColumn: nameof(PredictedSeries.ConfidenceLowerBound),
confidenceUpperBoundColumn: nameof(PredictedSeries.ConfidenceUpperBound)
);
Console.WriteLine("Training model");
ITransformer forecastTransformer = estimator.Fit(trainingData);
TimeSeriesPredictionEngine <BTC_TimeSeries, PredictedSeries> forecastEngine = forecastTransformer.CreateTimeSeriesEngine <BTC_TimeSeries, PredictedSeries>(mlContext);
PredictedSeries predictions = forecastEngine.Predict();
Console.WriteLine("last read time {0}: last read price {1}", lastTime, data.Last().Price);
for (int i = 0; i < predictions.ForecastedPrice.Count(); i++)
{
lastTime = lastTime.AddMinutes(15);
Console.WriteLine("{0} price: {1}, low: {2}, high: {3}", lastTime, predictions.ForecastedPrice[i].ToString(), predictions.ConfidenceLowerBound[i].ToString(), predictions.ConfidenceUpperBound[i].ToString());
}
float delta = predictedPrice - data.Last().Price;
Console.WriteLine("Delta, {0}", delta);
predictedPrice = predictions.ForecastedPrice[0];
forecastEngine.CheckPoint(mlContext, "forecastmodel.zip");
System.Threading.Thread.Sleep(300000);
c++;
}
Console.Read();
}
static ModelOutput Forecast(IEnumerable <ModelInput> testData, int horizon, TimeSeriesPredictionEngine <ModelInput, ModelOutput> forecaster, MLContext mlContext, string value)
{
ModelOutput forecast = forecaster.Predict();
IEnumerable <string> forecastOutput =
testData.TakeLast(horizon)
.Select((ModelInput values, int index) =>
{
string rentalDate = values.OpenTime.ToString();
float actualValue;
switch (value)
{
case "Close":
actualValue = values.Close;
break;
case "High":
actualValue = values.High;
break;
case "Low":
actualValue = values.Low;
break;
default:
actualValue = values.Close;
break;
}
float lowerEstimate = forecast.LowerBoundValue[index];
float estimate = forecast.ForecastedValue[index];
float upperEstimate = forecast.UpperBoundValue[index];
return($"Date: {rentalDate}\n" +
$"Actual {value}: {actualValue}\n" +
$"Forecast: {estimate}\n");
});
Console.WriteLine("Stock Forecast");
Console.WriteLine("---------------------");
foreach (var prediction in forecastOutput)
{
Console.WriteLine(prediction);
}
return(forecast);
}
static void Predict()
{
//prediction engine based on our fitted model
TimeSeriesPredictionEngine <BTCDataModel, PredictedSeriesDataModel> forecastEngine = forecastTransformer.CreateTimeSeriesEngine <BTCDataModel, PredictedSeriesDataModel>(mlContext);
//call to predict the next 5 minutes
PredictedSeriesDataModel predictions = forecastEngine.Predict();
//write our predictions
for (int i = 0; i < predictions.ForecastedPrice.Count(); i++)
{
lastTime = lastTime.AddMinutes(1);
Console.WriteLine("{0} price: {1}, low: {2}, high: {3}, actual: {4}", lastTime, predictions.ForecastedPrice[i].ToString(), predictions.ConfidenceLowerBound[i].ToString(), predictions.ConfidenceUpperBound[i].ToString(), testingData[i].Amount);
}
//instead of saving, we use checkpoint. This allows us to continue training with updated data and not need to keep such a large data set
//so we can append Jan. 2021 without having everythign before to train the model speeding up the process
forecastEngine.CheckPoint(mlContext, fileName);
}
public ModelOutput Predict()
{
return(timeSeriesPredictionEngine.Predict());
}
public IEnumerable <RatioAnalysis> Predict(IEnumerable <RatioAnalysis> data)
{
var mlContext = new MLContext(seed: 1);
IEstimator <ITransformer> costofgoodsForcaster = mlContext.Forecasting.ForecastBySsa(
outputColumnName: nameof(RatioAnalysisPrediction.Forecasted),
inputColumnName: nameof(RatioAnalysis.CostOfGoods), // This is the column being forecasted.
windowSize: 12, // Window size is set to the time period represented in the product data cycle; our product cycle is based on 12 months, so this is set to a factor of 12, e.g. 3.
seriesLength: data.Count(), // This parameter specifies the number of data points that are used when performing a forecast.
trainSize: data.Count(), // This parameter specifies the total number of data points in the input time series, starting from the beginning.
horizon: 3, // Indicates the number of values to forecast; 3 indicates that the next 3 months of product units will be forecasted.
confidenceLevel: 0.75f, // Indicates the likelihood the real observed value will fall within the specified interval bounds.
confidenceLowerBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceLowerBound), //This is the name of the column that will be used to store the lower interval bound for each forecasted value.
confidenceUpperBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceUpperBound)); //This is the name of the column that will be used to store the upper interval bound for each forecasted value.
IEstimator <ITransformer> inventoryForcaster = mlContext.Forecasting.ForecastBySsa(
outputColumnName: nameof(RatioAnalysisPrediction.Forecasted),
inputColumnName: nameof(RatioAnalysis.Inventory), // This is the column being forecasted.
windowSize: 12, // Window size is set to the time period represented in the product data cycle; our product cycle is based on 12 months, so this is set to a factor of 12, e.g. 3.
seriesLength: data.Count(), // This parameter specifies the number of data points that are used when performing a forecast.
trainSize: data.Count(), // This parameter specifies the total number of data points in the input time series, starting from the beginning.
horizon: 3, // Indicates the number of values to forecast; 3 indicates that the next 3 months of product units will be forecasted.
confidenceLevel: 0.75f, // Indicates the likelihood the real observed value will fall within the specified interval bounds.
confidenceLowerBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceLowerBound), //This is the name of the column that will be used to store the lower interval bound for each forecasted value.
confidenceUpperBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceUpperBound)); //This is the name of the column that will be used to store the upper interval bound for each forecasted value.
IEstimator <ITransformer> turnoverForcaster = mlContext.Forecasting.ForecastBySsa(
outputColumnName: nameof(RatioAnalysisPrediction.Forecasted),
inputColumnName: nameof(RatioAnalysis.Turnover), // This is the column being forecasted.
windowSize: 12, // Window size is set to the time period represented in the product data cycle; our product cycle is based on 12 months, so this is set to a factor of 12, e.g. 3.
seriesLength: data.Count(), // This parameter specifies the number of data points that are used when performing a forecast.
trainSize: data.Count(), // This parameter specifies the total number of data points in the input time series, starting from the beginning.
horizon: 3, // Indicates the number of values to forecast; 3 indicates that the next 3 months of product units will be forecasted.
confidenceLevel: 0.75f, // Indicates the likelihood the real observed value will fall within the specified interval bounds.
confidenceLowerBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceLowerBound), //This is the name of the column that will be used to store the lower interval bound for each forecasted value.
confidenceUpperBoundColumn: nameof(RatioAnalysisPrediction.ConfidenceUpperBound)); //This is the name of the column that will be used to store the upper interval bound for each forecasted value.
// Fit the forecasting model to the specified product's data series.
ITransformer costofgoodsTransformer = costofgoodsForcaster.Fit(mlContext.Data.LoadFromEnumerable(data));
ITransformer inventoryTransformer = inventoryForcaster.Fit(mlContext.Data.LoadFromEnumerable(data));
ITransformer turnoverTransformer = turnoverForcaster.Fit(mlContext.Data.LoadFromEnumerable(data));
// Create the forecast engine used for creating predictions.
TimeSeriesPredictionEngine <RatioAnalysis, RatioAnalysisPrediction> inventoryEngine = inventoryTransformer.CreateTimeSeriesEngine <RatioAnalysis, RatioAnalysisPrediction>(mlContext);
TimeSeriesPredictionEngine <RatioAnalysis, RatioAnalysisPrediction> turneroverEngine = turnoverTransformer.CreateTimeSeriesEngine <RatioAnalysis, RatioAnalysisPrediction>(mlContext);
TimeSeriesPredictionEngine <RatioAnalysis, RatioAnalysisPrediction> costofgoodEngine = costofgoodsTransformer.CreateTimeSeriesEngine <RatioAnalysis, RatioAnalysisPrediction>(mlContext);
// Get the prediction; this will include the forecasted turnover for the next 3 months since this
//the time period specified in the `horizon` parameter when the forecast estimator was originally created.
var turnoverPrediction = turneroverEngine.Predict();
var costPrediction = costofgoodEngine.Predict();
var inventoryPrediction = inventoryEngine.Predict();
var last = data.Last();
var retVal = data.ToList();
for (int i = 0; i < turnoverPrediction.Forecasted.Count(); i++)
{
retVal.Add(new RatioAnalysis
{
Date = last.Date.AddMonths(i + 1),
CostOfGoods = costPrediction.Forecasted[i],
CostOfGoodsDelta = costPrediction.ConfidenceUpperBound[i] - costPrediction.Forecasted[i],
Inventory = inventoryPrediction.Forecasted[i],
InventoryDelta = inventoryPrediction.ConfidenceUpperBound[i] - inventoryPrediction.Forecasted[i],
Turnover = turnoverPrediction.Forecasted[i],
TurnoverDelta = turnoverPrediction.ConfidenceUpperBound[i] - turnoverPrediction.Forecasted[i]
});
}
return(retVal);
}