BinaryClassificationCatalog.CalibratorsCatalog.Platt Metoda
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Přetížení
Platt(Double, Double, String) |
Přidá sloupec pravděpodobnosti zadáním kalibrátoru platt. |
Platt(String, String, String) |
Přidá sloupec pravděpodobnosti pomocí kalibrátoru trénovací desky. |
Platt(Double, Double, String)
Přidá sloupec pravděpodobnosti zadáním kalibrátoru platt.
public Microsoft.ML.Calibrators.FixedPlattCalibratorEstimator Platt (double slope, double offset, string scoreColumnName = "Score");
member this.Platt : double * double * string -> Microsoft.ML.Calibrators.FixedPlattCalibratorEstimator
Public Function Platt (slope As Double, offset As Double, Optional scoreColumnName As String = "Score") As FixedPlattCalibratorEstimator
Parametry
- slope
- Double
Sklon funkce exponentu sigmoidu.
- offset
- Double
Posun funkce exponentu sigmoidu.
- scoreColumnName
- String
Název sloupce skóre
Návraty
Příklady
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.ML;
namespace Samples.Dynamic.Trainers.BinaryClassification.Calibrators
{
public static class FixedPlatt
{
public static void Example()
{
// Create a new context for ML.NET operations. It can be used for
// exception tracking and logging, as a catalog of available operations
// and as the source of randomness. Setting the seed to a fixed number
// in this example to make outputs deterministic.
var mlContext = new MLContext(seed: 0);
// Download and featurize the dataset.
var data = Microsoft.ML.SamplesUtils.DatasetUtils
.LoadFeaturizedAdultDataset(mlContext);
// Leave out 10% of data for testing.
var trainTestData = mlContext.Data
.TrainTestSplit(data, testFraction: 0.3);
// Create data training pipeline for non calibrated trainer and train
// Naive calibrator on top of it.
var pipeline = mlContext.BinaryClassification.Trainers
.AveragedPerceptron();
// Fit the pipeline, and get a transformer that knows how to score new
// data.
var transformer = pipeline.Fit(trainTestData.TrainSet);
// Fit this pipeline to the training data.
// Let's score the new data. The score will give us a numerical
// estimation of the chance that the particular sample bears positive
// sentiment. This estimate is relative to the numbers obtained.
var scoredData = transformer.Transform(trainTestData.TestSet);
var outScores = mlContext.Data
.CreateEnumerable<ScoreValue>(scoredData, reuseRowObject: false);
PrintScore(outScores, 5);
// Preview of scoredDataPreview.RowView
// Score -0.09044361
// Score -9.105377
// Score -11.049
// Score -3.061928
// Score -6.375817
// Let's train a calibrator estimator on this scored dataset. The
// trained calibrator estimator produces a transformer that can
// transform the scored data by adding a new column names "Probability".
var calibratorEstimator = mlContext.BinaryClassification.Calibrators
.Platt(slope: -1f, offset: -0.05f);
var calibratorTransformer = calibratorEstimator.Fit(scoredData);
// Transform the scored data with a calibrator transfomer by adding a
// new column names "Probability". This column is a calibrated version
// of the "Score" column, meaning its values are a valid probability
// value in the [0, 1] interval representing the chance that the
// respective sample bears positive sentiment.
var finalData = calibratorTransformer.Transform(scoredData);
var outScoresAndProbabilities = mlContext.Data
.CreateEnumerable<ScoreAndProbabilityValue>(finalData,
reuseRowObject: false);
PrintScoreAndProbability(outScoresAndProbabilities, 5);
// Score -0.09044361 Probability 0.4898905
// Score -9.105377 Probability 0.0001167479
// Score -11.049 Probability 1.671815E-05
// Score -3.061928 Probability 0.04688989
// Score -6.375817 Probability 0.001786307
}
private static void PrintScore(IEnumerable<ScoreValue> values, int numRows)
{
foreach (var value in values.Take(numRows))
Console.WriteLine("{0, -10} {1, -10}", "Score", value.Score);
}
private static void PrintScoreAndProbability(
IEnumerable<ScoreAndProbabilityValue> values, int numRows)
{
foreach (var value in values.Take(numRows))
Console.WriteLine("{0, -10} {1, -10} {2, -10} {3, -10}", "Score",
value.Score, "Probability", value.Probability);
}
private class ScoreValue
{
public float Score { get; set; }
}
private class ScoreAndProbabilityValue
{
public float Score { get; set; }
public float Probability { get; set; }
}
}
}
Platí pro
Platt(String, String, String)
Přidá sloupec pravděpodobnosti pomocí kalibrátoru trénovací desky.
public Microsoft.ML.Calibrators.PlattCalibratorEstimator Platt (string labelColumnName = "Label", string scoreColumnName = "Score", string exampleWeightColumnName = default);
member this.Platt : string * string * string -> Microsoft.ML.Calibrators.PlattCalibratorEstimator
Public Function Platt (Optional labelColumnName As String = "Label", Optional scoreColumnName As String = "Score", Optional exampleWeightColumnName As String = Nothing) As PlattCalibratorEstimator
Parametry
- labelColumnName
- String
Název sloupce popisku
- scoreColumnName
- String
Název sloupce skóre
- exampleWeightColumnName
- String
Název ukázkového sloupce hmotnosti (volitelné).
Návraty
Příklady
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.ML;
namespace Samples.Dynamic.Trainers.BinaryClassification.Calibrators
{
public static class Platt
{
public static void Example()
{
// Create a new context for ML.NET operations. It can be used for
// exception tracking and logging, as a catalog of available operations
// and as the source of randomness. Setting the seed to a fixed number
// in this example to make outputs deterministic.
var mlContext = new MLContext(seed: 0);
// Download and featurize the dataset.
var data = Microsoft.ML.SamplesUtils.DatasetUtils
.LoadFeaturizedAdultDataset(mlContext);
// Leave out 10% of data for testing.
var trainTestData = mlContext.Data
.TrainTestSplit(data, testFraction: 0.3);
// Create data training pipeline for non calibrated trainer and train
// Naive calibrator on top of it.
var pipeline = mlContext.BinaryClassification.Trainers
.AveragedPerceptron();
// Fit the pipeline, and get a transformer that knows how to score new
// data.
var transformer = pipeline.Fit(trainTestData.TrainSet);
// Fit this pipeline to the training data.
// Let's score the new data. The score will give us a numerical
// estimation of the chance that the particular sample bears positive
// sentiment. This estimate is relative to the numbers obtained.
var scoredData = transformer.Transform(trainTestData.TestSet);
var outScores = mlContext.Data
.CreateEnumerable<ScoreValue>(scoredData, reuseRowObject: false);
PrintScore(outScores, 5);
// Preview of scoredDataPreview.RowView
// Score -0.09044361
// Score -9.105377
// Score -11.049
// Score -3.061928
// Score -6.375817
// Let's train a calibrator estimator on this scored dataset. The
// trained calibrator estimator produces a transformer that can
// transform the scored data by adding a new column names "Probability".
var calibratorEstimator = mlContext.BinaryClassification.Calibrators
.Platt();
var calibratorTransformer = calibratorEstimator.Fit(scoredData);
// Transform the scored data with a calibrator transfomer by adding a
// new column names "Probability". This column is a calibrated version
// of the "Score" column, meaning its values are a valid probability
// value in the [0, 1] interval representing the chance that the
// respective sample bears positive sentiment.
var finalData = calibratorTransformer.Transform(scoredData);
var outScoresAndProbabilities = mlContext.Data
.CreateEnumerable<ScoreAndProbabilityValue>(finalData,
reuseRowObject: false);
PrintScoreAndProbability(outScoresAndProbabilities, 5);
// Score -0.09044361 Probability 0.423026
// Score -9.105377 Probability 0.02139676
// Score -11.049 Probability 0.01014891
// Score -3.061928 Probability 0.1872233
// Score -6.375817 Probability 0.05956031
}
private static void PrintScore(IEnumerable<ScoreValue> values, int numRows)
{
foreach (var value in values.Take(numRows))
Console.WriteLine("{0, -10} {1, -10}", "Score", value.Score);
}
private static void PrintScoreAndProbability(
IEnumerable<ScoreAndProbabilityValue> values, int numRows)
{
foreach (var value in values.Take(numRows))
Console.WriteLine("{0, -10} {1, -10} {2, -10} {3, -10}", "Score",
value.Score, "Probability", value.Probability);
}
private class ScoreValue
{
public float Score { get; set; }
}
private class ScoreAndProbabilityValue
{
public float Score { get; set; }
public float Probability { get; set; }
}
}
}