تناولنا في بحثنا أحد اساليب البرمجة الخطية وهي الطريقة المبسطة لتقدير معلمات انموذج الانحدار الخطي عن طريق اختيار دالة الهدف التي تعمل على تقليل الحد الادنى لمجموع الاخطاء الناتجة من تقدير المعلمات بطريقة المربعات الصغرى الاعتيادية ( OLS) حيث سيتم في الطريقة المبسطة ( simplex) فرض قيود على نفس الاخطاء نفسها بهدف تصغيرها الى اقل ما يمكن للحصول على تقديرات افضل لمعلمات انموذج الانحدار الخطي . على اساس ان طريقة المربعات الصغرى الاعتيادية هي محاولة لتقدير معلمات انموذج الانحدار الخطي عن طريق تقليل مجموع المربعات من الاخطاء الى اقل مايمكن للحصول على افضل تقدير لتلك المعلمات. باستخدام اسلوب المحاكاة التجريبي لتوليد بيانات من انموذج الانحدار الخطي المفترض ومائة عينة تمت مقارنة النتائج تقديرات المعلمات بطريقة المربعات الصغرى الاعتيادية مع نتائج الطريقة المبسطة لتصغير مجموع الاخطاء مع وضع قيود على تلك الاخطاء . ومن خلال هذا البحث يمكن ان نستنتج ان طريقة المبسطة تعطي نتائج افضل في تقدير معلمات انموذج الانحدار الخطي من طريقة المربعات الصغرى الاعتيادية ضمن حالات مختلفة تم عرضها في الجانب التجريبي في المحاكاة . تضمن البحث ايضا موضوع تحليل الاتجاهات الزمنية باستخدام الطريقة المبسطة في انتاج وتسويق التمور في العراق كون هذا المحصول يشكل اهمية كبيرة في الدراسات الاقتصادية لما لها من علاقة وثيقة بموضوع الامن الغذائي .
تهدف هذه الدراسة إلى معرفة الفرق في التحصيل الدراسي في الكيمياء والاتجاه نحو العلوم بين طلاب التخصص العلمي وطلاب التخصص الصناعي الصف الأول كلية التربية ابن الهيثم، كذلك تهدف الدراسة إلى معرفة العلاقة بين التحصيل الدراسي في الكيمياء ودرجات اختبار نهاية الفصل في الكيمياء، والمعدل التراكمي بعد أخذ المقرر الدراسي والاتجاه نحو العلوم بالنسبة لطلاب التخصص العلمي وطلاب التخصص الصناعي.
لقد است
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