Ebru KILIÇ ÇAKMAK, Erhan GÜNEŞ, Mutlu TAHSİN

Web Sitesi Kullanılabilirlik Ölçeğinin Geliştirilmesi: Geçerlik, Güvenirlik Analizi ve Uygulama Sonuçları

Çalışmanın amacı, web sitelerinin kullanıcı algısına dayalı kullanılabilirlik düzeylerini belirlemeye yönelik bir “Web sitesi kullanılabilirlik ölçeği” geliştirmektir. Alanyazın taraması sonucunda kullanılabilirlikle ilgili boyutlar ortaya çıkarılmış ve bu bağlamda 53 soruluk madde havuzu oluşturulmuştur. Kapsam geçerliği için ölçek, 7 alan uzmanının görüşüne sunulmuştur. Uzman görüşleri doğrultusunda düzenlenen maddelerden oluşan taslak form, Gazi Üniversitesi Uzaktan Eğitim Meslek Yüksekokulu öğrenme yönetim sistemi web sitesini kullanan 245 öğrenciye uygulanmıştır. Kullanılabilirlik ölçeğinin yapı geçerliğini incelemek için Açımlayıcı ve Doğrulayıcı Faktör Analizi yöntemleri kullanılmış, güvenilirliklerinin belirlenmesi için de Cronbach alfa iç tutarlık katsayısı hesaplanmış, düzeltilmiş madde-toplam korelasyonu ve t testi kullanılarak üst %27 ile alt %27 grupların madde ortalamaları arasındaki farkların anlamlılığı incelenmiştir. Yapılan analizler sonucunda dört faktörlü yapıya sahip 25 maddeden oluşan kullanıcı algısına dayalı web sitesi kullanılabilirlik ölçeği elde edilmiştir. Son olarak, geliştirilen ölçek öğrenme yönetim sistemi web sitesinin kullanılabilirliğini belirlemek amacıyla 239 uzaktan eğitim öğrencisi üzerinde uygulanmış ve sonuçlar rapor edilmiştir.

Anahtar Kelimeler:

Kullanılabilirlik, gezinme kolaylığı, tasarım, erişim kolaylığı, kullanım kolaylığı, ölçek geliştirme

Developing a Web Site Usability Scale: The Validity and Reliability Analysis & Implementation Results

The aim of this research was to develop a “User perception based web site usability scale” to be used for assigning usability of web sites based on user perception. After a literature review dimensions of usability were found out. Subsequently a pool of items including a total of 53 items was collected in this context. The draft form which was developed according to 7 subject matter experts’ opinions, was applied on 245 students who had been using Gazi University Distance Education Vocational College LMS (Learning Management System) web site. Exploratory and confirmatory factor analysis methods were used to determine construct validity. For reliability, Cronbach alpha internal consistency coefficient was taken into account; corrected item-total correlation and t-test were used to examine significance between item averages of top %27 and bottom %27 groups. As a result of the analysis process, the user perception based web site usability scale, with a construct of four factors including of 25 items, was developed. Finally, the scale was applied on 239 e-learners in order to determine the usability level of the LMS web site which they had been using and results were reported.

Keywords:

Usability, ease of navigation, design, ease of access, ease of use, scale development,

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