What is Natural Language Processing
Learn the fundamental definition and scope of NLP as a field bridging computer science and linguistics.
AI
Linguistics
Text Analysis
Natural Language Processing (NLP) is a field of artificial intelligence that focuses on the interaction between computers and human language. It involves developing algorithms and models to understand, interpret, and generate human language in a valuable way.
# NLP involves multiple aspects
nlp_components = {
"Understanding": "Comprehend meaning from text",
"Generation": "Produce human-like text",
"Translation": "Convert between languages",
"Extraction": "Pull out specific information",
"Classification": "Categorize text content",
"Summarization": "Condense long texts"
}
# Example NLP task
text = "I love this movie! It's fantastic."
# NLP can determine: sentiment=positive, emotion=joy
NLP vs Computational Linguistics
Understand the relationship and differences between NLP and computational linguistics.
Computational Linguistics: Theory-focused, studies language as a computational system
NLP: Application-focused, builds practical systems for language tasks
Overlap: Both use computational methods for language processing
Computational Linguistics might ask: "How can we model the syntax of English using formal grammars?"
NLP might ask: "How can we build a system that accurately translates English to Spanish for business documents?"
Challenges in NLP
Explore the unique difficulties that make natural language processing complex and challenging.
Key NLP challenges: Ambiguity (multiple meanings), Context dependency, Variability in expression, Implicit knowledge requirements, Cultural and domain-specific language, and Real-world knowledge integration.
# Examples of NLP challenges
# 1. Ambiguity
sentence1 = "I saw a man with a telescope"
# Who has the telescope? The observer or the man?
# 2. Context dependency
sentence2 = "The bank is closed"
# Financial institution or river bank?
# 3. Sarcasm and irony
sentence3 = "Great! Another meeting..."
# Positive words, negative sentiment
# 4. Cultural references
sentence4 = "It's raining cats and dogs"
# Idiom meaning heavy rain, not literal animals
Applications and Use Cases
Discover the wide range of real-world applications where NLP creates value.
Search
Translation
Chatbots
Analytics
# Major NLP applications
applications = {
"Search Engines": {
"query_understanding": "What user wants",
"document_ranking": "Relevance scoring",
"snippet_generation": "Result summaries"
},
"Virtual Assistants": {
"speech_recognition": "Voice to text",
"intent_detection": "What user wants",
"response_generation": "Natural replies"
},
"Business Intelligence": {
"sentiment_analysis": "Customer opinions",
"trend_detection": "Topic monitoring",
"document_analysis": "Contract review"
}
}
NLP Pipeline Overview
Understand the typical stages involved in processing natural language data.
Text Input → Preprocessing → Tokenization → Linguistic Analysis → Feature Extraction → Machine Learning → Application Output
import nltk
from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.naive_bayes import MultinomialNB
# Complete NLP pipeline example
def nlp_pipeline(text):
# 1. Preprocessing
text = text.lower().strip()
# 2. Tokenization
tokens = nltk.word_tokenize(text)
# 3. Remove stopwords
stop_words = set(nltk.corpus.stopwords.words('english'))
filtered_tokens = [w for w in tokens if w not in stop_words]
# 4. Rejoin for vectorization
processed_text = ' '.join(filtered_tokens)
return processed_text
# Example usage
raw_text = "The movie was absolutely fantastic!"
processed = nlp_pipeline(raw_text)
print(processed) # "movie absolutely fantastic"
Text as Data
Learn how to think about text from a data science perspective and its unique properties.