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shashank ms
shashank ms

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LLM for Sentiment Analysis and Opinion Mining in Social Media

Social media sentiment analysis has moved beyond counting positive and negative keywords. Platforms like X, Reddit, and TikTok generate text full of sarcasm, code-switched language, and implicit context that classical lexicon models misclassify regularly. Large language models can capture these nuances, but production pipelines need more than a generic prompt. They require structured output, tolerant parsing, and an inference backend that remains cost-effective when you are processing thousands of lengthy user threads daily.

Why LLMs Outperform Classical Approaches for Social Sentiment

Classical tools such as VADER or TextBlob rely on lexicon scores and simple negation rules. They break down when users write sarcastically, use emerging slang, or mix languages within a single post. Large language models reason over context, not just word lists, which makes them far more robust for aspect-based sentiment analysis and emotion detection.

Social data is also inherently multilingual. A thread might begin in English, pivot to Spanish, and end with region-specific memes. Running separate monolingual pipelines is fragile. Oxlo.ai hosts Qwen 3 32B, a model built for multilingual reasoning and agent workflows, so a single endpoint can handle mixed-language content without hand-tuned language detection.

Designing a Prompt for Aspect-Based Sentiment Analysis

A good production prompt does not ask for a vague rating. It defines the aspects you care about, requests evidence, and sets a narrow output schema. For social media, you should also instruct the model to normalize slang and expand acronyms before judging sentiment.

Below is a system prompt template that targets product discussions on social channels:

You are a social media sentiment analyst.
Analyze the provided post and any replies for overall sentiment and aspect-level opinions.
Return strictly valid JSON with no markdown formatting.

Schema:
{
  "overall_sentiment": "positive" | "negative" | "neutral" | "mixed",
  "confidence": 0.0-1.0,
  "sarcasm_detected": boolean,
  "aspects": [
    {"target": "string", "sentiment": "...", "evidence": "exact quote"}
  ],
  "dominant_emotion": "anger" | "joy" | "sadness" | "fear" | "surprise" | "none"
}

Normalize slang and expand acronyms before judging sentiment.

Handling Social Media Noise with Structured Output

Raw LLM text is difficult to parse at scale. JSON mode lets you enforce a schema so that every response contains the same keys. This is critical when you are feeding sentiment results into a downstream analytics warehouse or real-time alerting system.

Social posts also contain noise: URLs, special characters, excessive emojis, and nested reply structures. By concatenating a post with its reply chain into a single prompt, you give the model conversational context. If you are analyzing visual memes or screenshots, vision-capable models such as Kimi K2.6 and Gemma 3 27B on Oxlo.ai can accept image inputs alongside text.

The following Python example uses the OpenAI SDK with Oxlo.ai as a drop-in replacement. It sends a post and optional replies, then returns parsed JSON:

import os
import json
from openai import OpenAI
from typing import List, Dict, Optional

client = OpenAI(
base_url="https://api.oxlo.ai/v1",
api_key=os.getenv("OXLO_API_KEY")
)

SYSTEM_PROMPT = """You are a social media sentiment analyst.
Analyze the provided post and any replies for overall sentiment and aspect-level opinions.
Return strictly valid JSON with no markdown formatting.
Schema:
{
"overall_sentiment": "positive" | "negative" | "neutral" | "mixed",
"confidence": 0.0-1.0,
"sarcasm_detected": boolean,
"aspects": [
{"target": "string", "sentiment": "...", "evidence": "exact quote"}
],
"dominant_emotion": "anger" | "joy" | "sadness" | "fear" | "surprise" | "none"

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