Σύγκριση μεθόδων

	Μηχανισμός Προσοχής	Ενσωματώσεις BERT	Ανάλυση Συναισθήματος	Vision Transformer
Πεδίο	Βαθιά Μάθηση	Εξόρυξη Κειμένου	Εξόρυξη Κειμένου	Βαθιά Μάθηση
Οικογένεια	Machine learning	Process / pipeline	Process / pipeline	Machine learning
Έτος προέλευσης	2015	2019	—	2021
Δημιουργός	Bahdanau, D.; Luong, M.T.	Devlin, Chang, Lee & Toutanova (Google AI)	—	Dosovitskiy, A. et al.
Τύπος	Neural attention layer (encoder-decoder)	Contextual transformer text-representation method	NLP text-classification task	Transformer architecture for images (self-attention over patches)
Θεμελιώδης πηγή	Bahdanau, D., Cho, K. & Bengio, Y. (2015). Neural Machine Translation by Jointly Learning to Align and Translate. ICLR.	Devlin, J., Chang, M.-W., Lee, K. & Toutanova, K. (2019). BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding. NAACL-HLT, 4171-4186.	Pang, B. & Lee, L. (2008). Opinion Mining and Sentiment Analysis. Foundations and Trends in Information Retrieval, 2(1-2), 1-135.	Dosovitskiy, A. et al. (2021). An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale. ICLR.
Εναλλακτικές ονομασίες	Dikkat Mekanizması (Bahdanau / Luong Attention), dikkat mekanizmasi, neural attention, additive attention	contextual embeddings, transformer embeddings, BERT Tabanlı Metin Gömülmeleri	opinion mining, polarity detection, duygu analizi	Görsel Transformer (ViT), görsel transformer, ViT, patch transformer for images
Συναφείς	5	4	3	5
Σύνοψη	The attention mechanism, introduced by Bahdanau, Cho and Bengio in 2015 and refined by Luong, Pham and Manning the same year, lets a sequence decoder dynamically learn which of the encoder's outputs to focus on at each step. Before the Transformer, it substantially improved machine-translation quality by freeing models from compressing an entire input into a single fixed vector.	BERT-based text embeddings, introduced by Devlin and colleagues at Google AI in 2019, turn text into context-sensitive dense vectors using a bidirectional Transformer encoder. Because the meaning of a word shifts with its context, BERT produces richer representations than static methods such as Word2Vec or topic models like LDA.	Sentiment analysis, also called opinion mining, is a natural-language-processing task that detects the emotional tone of text — typically classifying it as positive, negative, or neutral. It turns unstructured opinion text into structured, quantifiable polarity signals using one of three families of approaches: sentiment lexicons, trained machine-learning classifiers, or pretrained transformer models.	The Vision Transformer (ViT), introduced by Dosovitskiy and colleagues in 2021, splits an image into fixed-size patches, treats those patches as a sequence, and applies the Transformer self-attention mechanism to image classification. Given enough training data, it surpasses convolutional neural networks (CNNs).