يك روش دومرحلهاي براي تركيب طبقه‌بندها
محورهای موضوعی : مهندسی برق و کامپیوتر
سیدحسن نبوی کریزی
1
*
,
احسان‌اله کبیر
2
1 - آموزشكده فني حرفه‌اي شهيد منتظري مشهد
2 - دانشگاه تربیت مدرس
کلید واژه: ايجاد گوناگونياختلاط خبره‌هاگروه ذراتتركيب طبقه‌بندهاتركيب خطيبهينه‌سازي,
چکیده مقاله :
يادگيري دسته‌جمعي، يک رويکرد مؤثر در يادگيري ماشيني است كه در آن با تركيب نتايج چند طبقه‌بند سعي مي‌شود تقريب بهتري از يك طبقه‌بند بهينه فراهم شود. براي آنكه تركيب نتايج طبقه‌بندها مفيد واقع شود بايد طبقه‌بندهاي پايه ضمن برخورداري از كارآيي قابل قبول، داراي خطاهاي متفاوتي بوده و قاعده مناسبي براي تركيب نتايج آنها به كار گرفته شود. در اين مقاله يك روش دومرحلهاي براي تركيب نتايج طبقه‌بندها پيشنهاد مي‌شود كه در مرحله اول آن، با روش اختلاط خبره‌ها يك مجموعه طبقه‌بند با خطاهاي متفاوت ايجاد مي‌شود و در مرحله دوم با استفاده از الگوريتم بهينه‌سازي گروه ذرات، وزن‌هاي بهينه براي تركيب خطي نظرات آنها پيدا مي‌شوند. نتايج آزمايش‌هاي ما بر روي چند مجموعه داده متداول، نشان مي‌دهند كه روش پيشنهادي ما باعث افزايش كارآيي سيستم طبقه‌بندي مركب نسبت به روش‌هاي يادگيري مستقل و روش اختلاط خبره‌ها مي‌شود.
Ensemble learning is an effective machine learning method that improves the classification performance. In this method, the outputs of multiple classifiers are combined so that the better results can be attained. As different classifiers may offer complementary information about the classification, combining classifiers, in an efficient way, can achieve better results than any single classifier. Combining multiple classifiers is only effective if the individual classifiers are accurate and diverse. In this paper, we propose a two-stage method for classifiers combination. In the first stage, by mixture of experts strategy we produce different classifiers and in the second stage by using particle swarm optimization (PSO), we find the optimal weights for linear combination of them. Experimental results on different data sets show that proposed method outperforms the independent training and mixture of experts methods.
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