This study aims to compare parametric and nonparametric methods based on Item Response Theory in determining differential item functioning in polytomous scales. DIF analysis based on parametric IRT was conducted by using parameters comparison method. For nonparametric IRT analysis, DIF is determined by comparison of area indices pertaining to ICC obtained for reference and focal groups. The Comparisons were conducted on data sets from TIMSS 2011 8th Class students survey where data set pertaining to responses of students to "Attitudes Toward Mathematics" composing of samplings from Turkey and South Korea and it was determined if it incorporated DIF according to country and sex differences. It is observed that parametric and nonparametric methods produce generally similar results for DIF analysis in terms of countries. Nevertheless, DIF analysis results for country based sex groups differed according to techniques based on parametric and nonparametric IRT. Results of the study showed that items incorporating DIF differed as to preferred technique. This indicated importance of choosing the best technique in studies to detect whether scale items incorporates DIF or not.

Gen teknolojisi, bilgi sahibi olarak eylemlerimize yön vermemizi gerektiren çeşitli uygulama alanları (sağlık, tarım vb.) içermektedir. Bu durum öncelikle toplumu bu konularda eğitme görevini yerine getiren eğiticiler açısından incelendiğinde ayrı bir önem taşımaktadır. Gen teknolojisi hakkında bilgilenme ve okuryazarlık eğitim kurumları ve çeşitli bilgi kaynakları yolu ile olur. Bu çalışmanın amacı, biyoloji öğretmen adaylarının gen teknolojisine ilişkin sahip oldukları bilgi düzeylerinin incelenmesi ve gen teknolojisine ilişkin bilgilendikleri kaynakların belirlenmesidir. Çalışma 135 biyoloji öğretmen adayı ile gerçekleştirilmiştir. Araştırmada kullanılan likert tipi anket maddeleri için betimleyici analizler yapılmış, frekans ve yüzde değerleri çıkartılarak yorumlanmış ve çapraz tablo analizlerinden faydalanılmıştır. Çalışmada biyoloji öğretmen adaylarının gen teknolojisi konularında düşük bilgi seviyesinde oldukları (%69.6) ve gen teknolojisi ile ilgili ders almış olsun ya da olmasın kendilerini az bilgili olarak hissettikleri tespit edilmiştir. Öğretmen adayları, gen teknolojisi hakkında en çok (%60 ve üzeri) televizyon belgeselleri, alana yönelik dergiler, biyoloji/kimya öğretmenleri, üniversitelerden uzmanlar, televizyon ve gazetelerden bilgi almaktadırlar. The Level of Knowledge of Prospective Biology Teachers on Gene Technology and Their Source of InformationArticle Info Abstract DOI: 10.14527/pegegog.2014.022 The Gene Technology includes an area of various implementations (health, agriculture etc.) on which we shall have knowledge and which will be our guide in our actions. This is of particular importance notably when it is evaluated in terms of the instructors providing education on these issues to the public. Knowledge and literacy on gene technology is acquired through educational institutions and various sources of information. The aim of this study is to assess the level of knowledge of prospective biology teachers on gene technology, and to investigate the sources of knowledge on the related subject. 135 prospective biology teachers participated in this study. Descriptive analyses were carried out for the items, the frequencies were interpreted and cross tabulation analyses were used. The results of this study demonstrate that the prospective biology teachers possess predominantly a low-level knowledge on gene technology (69.6%) and mostly feel that their knowledge on gene technology is scanty, regardless of whether they have taken courses on the subject or not. The top sources of the prospective teachers (over 60% as frequency) are television documentaries on gene technology, and journals, biology/chemistry teachers and experts from universities on the related area. Giriş"Modern biyoteknoloji" olarak adlandırılan gen teknolojisi (GT) günlük hayatımızda gün geçtikçe daha fazla karşılaştığımız ve üzerinde bilgi ve yargı sahibi olmamız gereken bir alandır. Bu teknoloji dünyamızın sağlık, çevre, tarım, endüstriyel üretim ve farklı alanlarındaki sorunlarının çözümü ve geliştirilmesi için oldukça...

The purpose of this study is to prove the equitability of pre and post-tests with the Rasch Model and to provide the observability of individual and interindividual ability changes by evaluating the equated tests with stack analysis within the scope of the Rasch Measurement Theory. The pre-test and post-test data that are applied in this study were derived from the project named A Model Proposal to Increase Turkey's Success in the field of Mathematics in International Large-Scale Exams: Effectiveness of the Cognitive Diagnosis based Monitoring Model No. 115K531, which started on 15/11/2015 and was supported by the TUBİTAK SOBAG 3501 program.The tests were analyzed with the Rasch model, and the fit of the data to the Rasch model was evaluated, and then the Rasch Model and the Separate estimation-Common person method were applied for equating process. Lastly, individual and interindividual ability changes were observed by applying the stack analysis method with the Rasch model. As a result of the analysis of pre and post-tests with the Rasch model, it was concluded that they meet the requirements of the model. As a consequence of the equating process, the equitability of pre-test and post-test was proved, and it was observed that the individual and interindividual ability change could be evaluated by analyzing the pre-test and post-test data with the stack analysis method.

This study is based on the application of latent growth modeling, which is one of structural equation models on real data. Teachers' Sense of Efficacy Scale (TSES), which was previously adapted into Turkish was administered to 200 preservice teachers at different time intervals for three times and study data was collected. Measurement equivalence of TSES was analyzed over this data using secondorder latent growth models. For this aim, whether the scale achieved measurement equivalence at metric and scalar level was tested. The findings support that Teachers' Efficacy Scale has measurement equivalence in time. Time intervals between the applications of the scale were associated with school experience (internship programs) of preservice teachers. The applications were carried out before, during and after internship. It was found that preservice teachers' sense of efficacy increased in time and that as school experience increased belief towards professional sense of efficacy developed.

Abstract. [Purpose] To examine the distribution of and relationship between the Gross Motor Function, Manual Ability, and Communication Function Classification Systems in different limbs of children with spastic cerebral palsy. We also investigated whether the four predicting variables of gender, age, manual ability, and gross motor classifications could significantly predict effective and non-effective communicator groups in communication function. [Subjects and Methods] This retrospective cross-sectional study included 327 children with a mean age of 10.13 ± 4.09 years. Classifications were performed by an experienced pediatric physiotherapist.[Results] Gross motor function levels showed a strong correlation with manual ability levels (r s =0.78). Manual ability level was strongly correlated with communication function levels (r s =0.73), particularly in quadriplegic children (r s = 0.78). Gross motor function levels were moderately correlated with communication function levels (r s =0.71). Effective communicators in communication function showed more functional levels of manual ability and were determined by Gross Motor Function classifications. The variables were better at predicting ineffective communicators (91% correct) compared with effective communicators (85% correct). [Conclusion] Further studies are needed to relate these functional performance systems to the activity and participation levels as well as the quality of life, desires, and participation of the subjects.