يعد أنموذج الانحدار اللوجستي من نماذج الانحدار المهمة، حيث يلقى اهتماماً واضحاً في معظم الدراسات التي تأخذ طابعاً اكثر تقدماً في عملية التحليل الاحصائي. أن طرائق التقدير الاعتيادية تفشل في التعامل مع البيانات التي تتضمن وجود القيم الشاذة حيث أن لها تأثير غير مرغوب على النتائج. سنستعرض في هذا البحث طرائق لتقدير معلمات انموذج الانحدار اللوجستي وهذه الطرائق هي: طريقة مقدر لابلاس (Laplace estimator) (LP-) وطريقة مقدر هوبر الحصين (Huber estimator) (H) . اذ تم اجراء المقارنة بين هاتين الطريقتين من خلال أسلوب المحاكاة وبأستعمال معيار المقارنة متوسط مربعات الخطأ (MSE) بنسب مختلفة من التلوث ولحجوم عينات مختلفة للوصول الى الطريقة الأفضل في تقدير المعلمات. واتضح من خلال المقارنة أن طريقة (H) هي الأفضل في تقدير معلمات أنموذج الانحدار اللوجستي .
يناقش هذا البحث مشكلة التعدد الخطي شبه التام في انموذج الانحدار اللاخطي ( انموذج الانحدار اللوجستي المتعدد) ، عندما يكون المتغير المعتمد متغير نوعيا يمثل ثنائي الاستجابة اما ان يساوي واحد لحدوث استجابة او صفر لعدم حدوث استجابة ، من خلال استعمال مقدرات المركبات الرئيسية التكرارية(IPCE) التي تعتمد على الاوزان الاعتيادية والاوزان البيزية الشرطية .
اذ تم تطبيق مقدرات هذا ا
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