Yeterlilik düzeyine göre sözcüksel yoğunluk, çeşitlilik ve sıklık: A1 ve C2 derlemlerinin karşılaştırılması

Öz

Bu çalışma, A1 ve C2 düzeyindeki yazılı metinlerde sözcüksel yoğunluk, sözcüksel çeşitlilik ve sözcük sıklığı dağılımlarını karşılaştırarak sözcük zenginliğinde gelişimsel farklılıkları incelenmiştir. Nicel bir derlem-dilbilimsel tasarım kullanılmış, sıklık bandı kapsama oranı, sözcük ailesi artışı, tür–örnek oranı, sözcüksel yoğunluk ve okunurluk puanlarını yeterlilik düzeyleri arasında değerlendirmek için RANGE ve Textalyser uygulanmıştır. Bulgular, sözcüksel yoğunluk, sözcüksel çeşitlilik ve sözcük sıklığı yönünden belirgin niteliksel farklılıkları ortaya koymaktadır: A1 düzeyindeki metinler büyük ölçüde en sık kullanılan 1.000 sözcüğe dayanırken, C2 derlemi Liste 2 ve Liste 3 sözcüklerinin önemli ölçüde daha geniş kullanımını, ayrıca akademik ve düşük sıklıklı sözcük ailelerinden belirgin biçimde daha fazla sözcük içerdiğini göstermiştir. Sözcüksel yoğunluk A1 metinlerinde daha yüksek bulunmuştur. Bu durum daha kısa ve yapısal açıdan daha basit metinleri yansıtırken; C2 metinlerinde artan sözdizimsel ayrıntılanma ve işlev sözcüklerinin daha fazla kullanımı nedeniyle daha düşük yoğunluk gözlenmiştir. Tür–örnek oranı A1’den C2’ye yalnızca sınırlı bir artış göstermiş, bu sonuç sözcük çeşitliliğinin metin uzunluğuna duyarlı bir ölçüt olmasına ilişkin bilinen sınırlamalarla uyumlu bulunmuştur. Okunabilirlik indeksleri yönünden iki derlem arasında önemli bir farklılaşma olduğu tespit edilmiştir. C2 metinlerinin anlamlı ölçüde daha karmaşık olduğu gözlemlenmiştir. Çalışma, sıklık bandı dağılımı ve sözcük ailesi genişlemesini sözcük gelişiminin en duyarlı göstergeleri olarak vurgulamaktadır. Ayrıca, ikinci dil yazımında sözcüksel zenginliğin çok boyutlu niteliğini ortaya koymaktadır.

Anahtar Kelimeler

• Sözcüksel yoğunluk
• Sözcüksel çeşitlilik
• Sözcük sıklığı
• Sözcüksel zenginlik
• Tür-örnek oranı
• Sözcük ailesi genişlemesi
• Okunabilirlik

Lexical density, diversity, and frequency across proficiency: a corpus-based comparison of A1 and C2 corpora

Öz

This study investigates developmental differences in lexical richness by comparing lexical density, lexical diversity, and vocabulary frequency distributions in A1 and C2 English texts by beginner and advanced level university students. Using a quantitative corpus-linguistic design, RANGE and Textalyser were employed to examine frequency-band coverage, word-family growth, type–token ratio, lexical density, and readability scores across proficiency levels. The findings reveal clear contrasts in vocabulary sophistication: A1 texts relied overwhelmingly on the most frequent 1,000 words, whereas the C2 corpus demonstrated substantially greater use of List 2 and List 3 vocabulary, including markedly larger inventories of academic and low-frequency word families. Lexical density was higher in A1 texts, reflecting shorter and structurally simpler compositions, while C2 texts exhibited lower density due to increased syntactic elaboration and greater use of function words. Although lexical diversity showed only a modest increase from A1 to C2, this result aligns with known limitations of TTR as a length-sensitive metric. Readability indices further distinguished the two groups, with C2 texts displaying significantly higher complexity. The study highlights frequency-band distribution and word-family expansion as the most sensitive indicators of lexical development and underscores the multidimensional nature of lexical richness in second-language writing.

Anahtar Kelimeler

• Lexical density
• Lexical diversity
• Vocabulary frequency
• Lexical richness
• Type-token ratio
• Word-family growth
• Readability

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