54 lines
1.6 KiB
C#
54 lines
1.6 KiB
C#
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/*
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* BotSharp.NLP Library
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* Copyright (C) 2018 Haiping Chen
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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using System;
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using System.Collections.Generic;
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using System.Text;
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namespace BotSharp.NLP.Classify
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{
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/// <summary>
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/// Lidstone smoothing, is a technique used to smooth categorical data.
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/// Given an observation x = (x1, …, xd) from a multinomial distribution with N trials, a "smoothed" version of the data gives the estimator:
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/// Refer https://en.wikipedia.org/wiki/Additive_smoothing
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/// </summary>
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public class Lidstone : IEstimator
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{
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/// <summary>
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/// x = (x1, …, xd)
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/// </summary>
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private int _d;
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/// <summary>
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/// α > 0 is the smoothing parameter
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/// </summary>
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private float _a;
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/// <summary>
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/// N trials
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/// </summary>
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private int _N;
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public Lidstone(float alpha, int bins)
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{
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_a = alpha;
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_d = bins;
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}
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}
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}
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