Peak flow rates of school children and environmental factors : mixed-effects modelling based on clusters of environmental variables
المؤلف
المصدر
Journal of Statistical Sciences
العدد
المجلد 1، العدد 1 (31 ديسمبر/كانون الأول 2009)، ص ص. 39-59، 21ص.
الناشر
المعهد العربي للتدريب و البحوث الإحصائية
تاريخ النشر
2009-12-31
دولة النشر
الأردن
عدد الصفحات
21
التخصصات الرئيسية
العلوم الاجتماعية (متداخلة التخصصات)
الموضوعات
الملخص EN
The purpose of this study is to demonstrate a new approach That uses model-based clustering of environmental variables instead of the variables themselves (as a method of data reduction), and to develop a multi-level model based on these clusters in order to investigate the relationship between groups of environmental variables and peak flow rate for school children.
The approach is applied to the same data in ward et al (2002) in which the peak flow rates were twice daily (am and pm) recorded for a period of 56 consecutive days of a cohort of 150, 9 years old, children was selected at five schools in Birmingham and sand well.
Our approach involves a modeling strategy carried on in two major stages, namely; model-based clustering based on expectation maximization (em) algorithm to reduce the huge number of variables, and residual maximum likelihood is then applied to a mixed-effects multilevel model.
Stage one reduced the 42 independent variables and their lags to 5 main groups.
In stage two, investigated the relations between these groups and the peak flow as a dependent variable.
Our results reveal the followings: the higher the pollution the lower the peak flow, one specific school has shown a common low peak flow among the children, and we find as expected significant difference between morning and evening peak flow.
نمط استشهاد جمعية علماء النفس الأمريكية (APA)
Husayn, Shakir. 2009. Peak flow rates of school children and environmental factors : mixed-effects modelling based on clusters of environmental variables. Journal of Statistical Sciences،Vol. 1, no. 1, pp.39-59.
https://search.emarefa.net/detail/BIM-182500
نمط استشهاد الجمعية الأمريكية للغات الحديثة (MLA)
Husayn, Shakir. Peak flow rates of school children and environmental factors : mixed-effects modelling based on clusters of environmental variables. Journal of Statistical Sciences Vol. 1, no. 1 (Jul. / Dec. 2009), pp.39-59.
https://search.emarefa.net/detail/BIM-182500
نمط استشهاد الجمعية الطبية الأمريكية (AMA)
Husayn, Shakir. Peak flow rates of school children and environmental factors : mixed-effects modelling based on clusters of environmental variables. Journal of Statistical Sciences. 2009. Vol. 1, no. 1, pp.39-59.
https://search.emarefa.net/detail/BIM-182500
نوع البيانات
مقالات
لغة النص
الإنجليزية
الملاحظات
Includes appendix : p. 55-59
رقم السجل
BIM-182500
قاعدة معامل التأثير والاستشهادات المرجعية العربي "ارسيف Arcif"
أضخم قاعدة بيانات عربية للاستشهادات المرجعية للمجلات العلمية المحكمة الصادرة في العالم العربي
تقوم هذه الخدمة بالتحقق من التشابه أو الانتحال في الأبحاث والمقالات العلمية والأطروحات الجامعية والكتب والأبحاث باللغة العربية، وتحديد درجة التشابه أو أصالة الأعمال البحثية وحماية ملكيتها الفكرية. تعرف اكثر