LLMs: Transformers, GPT, GPT2, GPT3 and chatGPT
LLMs stand for "Large Language Models". LLMs are a type of neural network architecture that are trained on massive amounts of text data to generate human-like text or perform natural language processing (NLP) tasks such as language translation, text classification, and question-answering.
LLMs are typically based on the Transformer architecture, which was introduced by Google in 2017 and is used by models such as GPT (Generative Pre-trained Transformer) and BERT (Bidirectional Encoder Representations from Transformers). The Transformer architecture uses self-attention mechanisms to process sequential data, such as text and can capture long-range dependencies and contextual information in the input data.
LLMs have gained popularity in recent years due to their ability to generate coherent and natural-sounding text, which has significant implications for applications such as chatbots, automated content generation, and natural language understanding. However, LLMs also raise concerns about ethical and social implications, including potential biases in the training data and the ability to generate fake or misleading information.
What's Transformer?
Transformers have revolutionized the field of natural language processing (NLP) and have been instrumental in the development of large language models such as GPT-3 and GPT-4. In this blog, we will discuss the history and evolution of Transformers, GPT, GPT-3, and GPT-4.
Transformers were first introduced by Vaswani et al. in the paper "Attention Is All You Need" in 2017. The paper introduced the Transformer architecture, which was a departure from the traditional recurrent neural networks (RNNs) and convolutional neural networks (CNNs) used in NLP tasks. The Transformer architecture is based on the idea of self-attention, where each word in a sentence is given attention weights based on its relationship with other words in the sentence. This attention mechanism allows the Transformer to capture long-range dependencies and improve the performance of NLP models.
GPT
The Transformer architecture was used to develop the GPT (Generative Pre-trained Transformer) model in 2018. GPT was trained on a massive corpus of text data using an unsupervised learning approach. The model was pre-trained on a large corpus of text data and fine-tuned on downstream NLP tasks such as language modelling, question-answering, and text completion. GPT-1 achieved state-of-the-art performance on several NLP benchmarks.
GPT-2
In 2019, OpenAI released GPT-2, an improved version of GPT-1 that had 1.5 billion parameters, making it one of the largest language models at the time. GPT-2 was trained on a massive corpus of text data and could generate coherent and fluent text that was almost indistinguishable from the human-written text. However, due to concerns about the potential misuse of the model, OpenAI only released a limited version of GPT-2.
GPT-3
In 2020, OpenAI released GPT-3, which was a massive leap in the size and performance of language models. GPT-3 had 175 billion parameters, making it the largest language model at the time. The model was pre-trained on a massive corpus of text data and could perform several NLP tasks without any fine-tuning. GPT-3 could generate coherent and fluent text, translate languages, answer questions, and even generate computer code. The model was a breakthrough in NLP and generated a lot of excitement in the research community.
GPT-3.5 or chatGPT
The architecture consists of multiple layers of multi-headed self-attention and feedforward neural networks. In each layer, the self-attention mechanism allows the model to weigh the importance of each token in the sequence with respect to the others, while the feedforward network applies non-linear transformations to the input features. This combination of self-attention and feedforward layers enables the model to capture long-range dependencies and contextual information in the input data.
The pre-training phase of ChatGPT involves training the model on a massive corpus of text data using an unsupervised learning approach. During pre-training, the model learns to predict the next word in a sequence based on the previous words. This pre-training enables the model to acquire a general understanding of the structure and semantics of natural language.
The fine-tuning phase of ChatGPT involves training the model on specific downstream tasks, such as language translation, text classification, or question-answering. During fine-tuning, the model adapts its pre-trained knowledge to the specific task by adjusting the parameters of the network. Fine-tuning allows ChatGPT to achieve state-of-the-art performance on a wide range of NLP tasks.
In summary, ChatGPT is a large language model based on the GPT architecture that uses a self-attention mechanism to process sequential data, such as text. The model is pre-trained on a massive corpus of text data using an unsupervised learning approach and can be fine-tuned on specific downstream tasks to achieve state-of-the-art performance.