Local sentiment analysis upload.

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戒酒的李白
2025-08-23 15:55:07 +08:00
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# 微博情感识别模型-GPT2-LoRA微调
## 项目说明
这是一个基于GPT2的微博情感二分类模型,采用LoRALow-Rank Adaptation)微调技术。通过PEFT库实现的LoRA微调,只需训练极少量参数就可以让模型适应情感分析任务,大幅降低计算资源需求和模型体积。
## 数据集
使用微博情感数据集(weibo_senti_100k),包含约10万条带情感标注的微博内容,正负向评论各约5万条。数据集标签:
- 标签0:负面情感
- 标签1:正面情感
## 文件结构
```
GPT2-Lora/
├── train.py # 训练脚本(基于PEFT库的LoRA实现)
├── predict.py # 预测脚本(交互式使用)
├── requirements.txt # 依赖包列表
├── models/ # 本地存储的预训练模型
│ └── gpt2-chinese/ # 中文GPT2模型及配置
├── dataset/ # 数据集目录
│ └── weibo_senti_100k.csv # 微博情感数据集
└── best_weibo_sentiment_lora/ # 训练好的LoRA权重(训练后生成)
```
## 技术特点
1. **极度参数高效**:相比全参数微调,仅训练约0.1%-1%的参数
2. **使用PEFT库**:基于Hugging Face官方的参数高效微调库,稳定可靠
3. **模型性能保持**:在仅训练极少参数的情况下,保持良好的分类性能
4. **部署友好**:LoRA权重文件小,便于模型部署和分享
## LoRA技术优势
LoRA (Low-Rank Adaptation) 是目前最流行的参数高效微调技术:
1. **超低参数量**:通过低秩分解,将大矩阵分解为两个小矩阵的乘积
2. **插件式设计**:LoRA权重可以动态加载和卸载,一个基础模型支持多个任务
3. **训练速度快**:参数少,训练时间短,内存占用小
4. **无损原模型**:原始预训练模型权重保持不变,避免灾难性遗忘
## 环境依赖
安装所需依赖:
```bash
pip install -r requirements.txt
```
主要依赖包:
- Python 3.8+
- PyTorch 1.13+
- Transformers 4.28+
- PEFT 0.4+
- Pandas, NumPy, Scikit-learn
## 使用方法
### 1. 安装依赖
```bash
pip install -r requirements.txt
```
### 2. 训练模型
```bash
python train.py
```
训练过程会自动:
- 下载并本地保存中文GPT2预训练模型
- 加载微博情感数据集
- 使用LoRA技术训练模型
- 保存最佳LoRA权重到 `./best_weibo_sentiment_lora/`
### 3. 情感分析预测
```bash
python predict.py
```
运行后将进入交互模式:
- 在控制台输入要分析的微博文本
- 系统会返回情感分析结果(正面/负面)和置信度
- 输入'q'退出程序
## 模型配置
- **基础模型**: `uer/gpt2-chinese-cluecorpussmall` 中文预训练模型
- **模型本地保存路径**: `./models/gpt2-chinese/`
- **LoRA配置**:
- rank (r): 8 - 低秩矩阵的秩
- alpha: 32 - 缩放因子
- target_modules: ["c_attn", "c_proj"] - 目标线性层
- dropout: 0.1 - 防止过拟合
## 性能对比
| 方法 | 可训练参数占比 | 模型文件大小 | 训练时间 | 推理速度 |
|------|----------------|--------------|----------|----------|
| 全参数微调 | 100% | ~500MB | 长 | 慢 |
| Adapter微调 | ~3% | ~50MB | 中等 | 中等 |
| **LoRA微调** | **~0.5%** | **~2MB** | **短** | **快** |
## 使用示例
```
使用设备: cuda
LoRA模型加载成功!
============= 微博情感分析 (LoRA版) =============
输入微博内容进行分析 (输入 'q' 退出):
请输入微博内容: 这部电影真是太好看了,我非常喜欢!
预测结果: 正面情感 (置信度: 0.9876)
请输入微博内容: 服务态度差,价格还贵,一点都不推荐
预测结果: 负面情感 (置信度: 0.9742)
请输入微博内容: q
```
## 注意事项
1. **首次运行**:首次运行 `train.py` 时会自动下载预训练模型,请确保网络连接
2. **GPU推荐**:虽然LoRA参数少,但建议使用GPU加速训练
3. **模型加载**:预测时需要先有训练好的LoRA权重文件
4. **兼容性**:基于PEFT库实现,与Hugging Face生态系统完全兼容
## 扩展功能
- **多任务支持**:可以为不同任务训练不同的LoRA权重,共享同一个基础模型
- **权重合并**:可以将多个LoRA权重合并,或将LoRA权重合并到基础模型中
- **动态切换**:支持运行时动态加载和切换不同的LoRA权重
## 技术原理
LoRA通过在原始线性层旁边添加两个小的矩阵A和B,使得:
```
h = W₀x + BAx
```
其中:
- W₀是冻结的预训练权重
- B ∈ ℝᵈˣʳ, A ∈ ℝʳˣᵏ是可训练的低秩矩阵
- r << min(d,k),大大减少了参数量
这种设计既保持了预训练模型的知识,又能高效地适应新任务。
@@ -0,0 +1,280 @@
{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# weibo_senti_100k 说明\n",
"0. **下载地址:** [百度网盘](https://pan.baidu.com/s/1DoQbki3YwqkuwQUOj64R_g)\n",
"1. **数据概览:** 10 万多条,带情感标注 新浪微博,正负向评论约各 5 万条\n",
"2. **推荐实验:** 情感/观点/评论 倾向性分析\n",
"2. **数据来源:** [新浪微博](https://weibo.com/)\n",
"3. **原数据集:** [新浪微博,情感分析标记语料共12万条](https://download.csdn.net/download/weixin_38442818/10214750),网上搜集,具体作者、来源不详\n",
"4. **加工处理:**\n",
" 1. 将原来的 2 份文档,整合成 1 份 csv 文件\n",
" 2. 编码统一为 UTF-8\n",
" 3. 去重"
]
},
{
"cell_type": "code",
"execution_count": 13,
"metadata": {},
"outputs": [],
"source": [
"import pandas as pd"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"path = 'weibo_senti_100k_文件夹_所在_路径'"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# 1. weibo_senti_100k.csv"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## 加载数据"
]
},
{
"cell_type": "code",
"execution_count": 15,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"评论数目(总体):119988\n",
"评论数目(正向):59993\n",
"评论数目(负向):59995\n"
]
}
],
"source": [
"pd_all = pd.read_csv(path + 'weibo_senti_100k.csv')\n",
"\n",
"print('评论数目(总体):%d' % pd_all.shape[0])\n",
"print('评论数目(正向):%d' % pd_all[pd_all.label==1].shape[0])\n",
"print('评论数目(负向):%d' % pd_all[pd_all.label==0].shape[0])"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## 字段说明\n",
"\n",
"| 字段 | 说明 |\n",
"| ---- | ---- |\n",
"| label | 1 表示正向评论,0 表示负向评论 |\n",
"| review | 微博内容 |"
]
},
{
"cell_type": "code",
"execution_count": 16,
"metadata": {},
"outputs": [
{
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" label review\n",
"62050 0 太过分了@Rexzhenghao //@Janie_Zhang:招行最近负面新闻越来越多呀...\n",
"68263 0 希望你?得好?我本"?肥血?史"[晕][哈哈]@Pete三姑父\n",
"81472 0 有点想参加????[偷?]想安排下时间再决定[抓狂]//@黑晶晶crystal: @细腿大羽...\n",
"42021 1 [给力]感谢所有支持雯婕的芝麻![爱你]\n",
"7777 1 2013最后一天,在新加坡开心度过,向所有的朋友们问声:新年快乐!2014年,我们会更好[调...\n",
"100399 0 大中午出门办事找错路,曝晒中。要多杯具有多杯具。[泪][泪][汗]\n",
"82398 0 马航还会否认吗?到底在隐瞒啥呢?[抓狂]//@头条新闻: 转发微博\n",
"106423 0 克罗地亚球迷很爱放烟火!球又没进,就硝烟四起。[晕]\n",
"24798 1 [抱抱]福芦 TangRoulou 吉祥书 8.8折优惠 >>> http://t.cn/z...\n",
"6598 1 回复@钱旭明QXM:[嘻嘻][嘻嘻] //@钱旭明QXM:杨大哥[good][good][g...\n",
"53920 1 人家这脸长的!!!!!![哈哈]\n",
"15587 1 这个价不算高,和一天内训相比相差无几。。[哈哈]//@博通传媒v: 6个月!一个月工资1万,...\n",
"101237 0 终于收工啦,脚丫子快冻掉了[泪][泪][泪]\n",
"82449 0 我决定从今天开始我想吃什么就去吃什么,一个人吃也无所谓,重点是不要因为别人的意见委屈了自己[...\n",
"32537 1 飘雪的北京 需要双份早餐.......//@美食天下: [哈哈]//@王淼Margay: 屁...\n",
"10630 1 [耶],这个太赞了,生活大爆炸第六季马上要出啦[鼓掌] //@-郑瑜-:这个不错 //@经典...\n",
"85130 0 刚追完#倾世皇妃#,#千山暮雪#又紧随其后,网速和更新速度都太不给力,尽管我看过原著,还是焦...\n",
"105956 0 晚上看金二胖?察前?,推出的火炮基座?糟了,可以PK了[泪] //@艾米粒er: //@wi...\n",
"72391 0 必须把中国足球的伟大,用我的职业演说出来 //@袁腾飞:[泪]\n",
"10761 1 [鼓掌] //@宁波香格里拉大酒店: 小编来答疑,周五晚惊艳全场的树根蛋糕到底有多长?蛋糕全..."
]
},
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"metadata": {},
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}
],
"source": [
"pd_all.sample(20)"
]
}
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@@ -0,0 +1,107 @@
import torch
from transformers import GPT2ForSequenceClassification, BertTokenizer
from peft import PeftModel
import os
import re
def preprocess_text(text):
return text
def main():
# 设置设备
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
print(f"使用设备: {device}")
# 模型和权重路径
base_model_path = './models/gpt2-chinese'
lora_model_path = './best_weibo_sentiment_lora'
print("加载模型和tokenizer...")
# 检查LoRA模型是否存在
if not os.path.exists(lora_model_path):
print(f"错误: 找不到LoRA模型路径 {lora_model_path}")
print("请先运行 train.py 进行训练")
return
# 加载tokenizer
try:
tokenizer = BertTokenizer.from_pretrained(base_model_path)
if tokenizer.pad_token is None:
tokenizer.pad_token = '[PAD]'
except Exception as e:
print(f"加载tokenizer失败: {e}")
print("请确保models/gpt2-chinese目录包含tokenizer文件")
return
# 加载基础模型
try:
base_model = GPT2ForSequenceClassification.from_pretrained(
base_model_path,
num_labels=2
)
base_model.config.pad_token_id = tokenizer.pad_token_id
except Exception as e:
print(f"加载基础模型失败: {e}")
print("请确保models/gpt2-chinese目录包含模型文件")
return
# 加载LoRA权重
try:
model = PeftModel.from_pretrained(base_model, lora_model_path)
model.to(device)
model.eval()
print("LoRA模型加载成功!")
except Exception as e:
print(f"加载LoRA权重失败: {e}")
print("请确保LoRA权重文件存在且格式正确")
return
print("\n============= 微博情感分析 (LoRA版) =============")
print("输入微博内容进行分析 (输入 'q' 退出):")
while True:
text = input("\n请输入微博内容: ")
if text.lower() == 'q':
break
if not text.strip():
print("输入不能为空,请重新输入")
continue
try:
# 预处理文本
processed_text = preprocess_text(text)
# 对文本进行编码
encoding = tokenizer(
processed_text,
max_length=128,
padding='max_length',
truncation=True,
return_tensors='pt'
)
# 转移到设备
input_ids = encoding['input_ids'].to(device)
attention_mask = encoding['attention_mask'].to(device)
# 预测
with torch.no_grad():
outputs = model(input_ids=input_ids, attention_mask=attention_mask)
logits = outputs.logits
probabilities = torch.softmax(logits, dim=1)
prediction = torch.argmax(probabilities, dim=1).item()
# 输出结果
confidence = probabilities[0][prediction].item()
label = "正面情感" if prediction == 1 else "负面情感"
print(f"预测结果: {label} (置信度: {confidence:.4f})")
except Exception as e:
print(f"预测时发生错误: {e}")
continue
if __name__ == "__main__":
main()
@@ -0,0 +1,10 @@
torch>=1.13.0
transformers>=4.28.0
peft>=0.4.0
pandas>=1.5.0
numpy>=1.21.0
scikit-learn>=1.0.0
tqdm>=4.64.0
datasets>=2.0.0
accelerate>=0.20.0
safetensors>=0.3.0
@@ -0,0 +1,283 @@
import os
import random
import numpy as np
import pandas as pd
import torch
import torch.nn as nn
from torch.utils.data import Dataset, DataLoader
from transformers import (
GPT2ForSequenceClassification,
BertTokenizer,
get_linear_schedule_with_warmup,
TrainingArguments,
Trainer
)
from torch.optim import AdamW
from sklearn.model_selection import train_test_split
from sklearn.metrics import accuracy_score, f1_score
from tqdm import tqdm
# 导入PEFT库中的LoRA相关组件
from peft import LoraConfig, TaskType, get_peft_model
# 设置随机种子
def set_seed(seed):
random.seed(seed)
np.random.seed(seed)
torch.manual_seed(seed)
if torch.cuda.is_available():
torch.cuda.manual_seed_all(seed)
set_seed(42)
# 定义微博情感分析数据集
class WeiboSentimentDataset(Dataset):
def __init__(self, reviews, labels, tokenizer, max_length=128):
self.reviews = reviews
self.labels = labels
self.tokenizer = tokenizer
self.max_length = max_length
def __len__(self):
return len(self.reviews)
def __getitem__(self, idx):
review = str(self.reviews[idx])
label = self.labels[idx]
encoding = self.tokenizer(
review,
max_length=self.max_length,
padding='max_length',
truncation=True,
return_tensors='pt'
)
return {
'input_ids': encoding['input_ids'].flatten(),
'attention_mask': encoding['attention_mask'].flatten(),
'labels': torch.tensor(label, dtype=torch.long)
}
# 训练函数
def train_model(model, train_dataloader, val_dataloader, optimizer, scheduler, device, epochs=3):
best_f1 = 0.0
for epoch in range(epochs):
print(f"======== Epoch {epoch+1} / {epochs} ========")
model.train()
total_loss = 0
# 训练循环
progress_bar = tqdm(train_dataloader, desc="Training", position=0, leave=True)
for batch in progress_bar:
# 将数据移到GPU
batch = {k: v.to(device) for k, v in batch.items()}
# 清零梯度
optimizer.zero_grad()
# 前向传播
outputs = model(
input_ids=batch['input_ids'],
attention_mask=batch['attention_mask'],
labels=batch['labels']
)
loss = outputs.loss
total_loss += loss.item()
# 反向传播
loss.backward()
# 梯度裁剪,防止梯度爆炸
torch.nn.utils.clip_grad_norm_(model.parameters(), 1.0)
# 参数更新
optimizer.step()
scheduler.step()
# 更新进度条
progress_bar.set_postfix({"loss": loss.item()})
# 计算平均训练损失
avg_train_loss = total_loss / len(train_dataloader)
print(f"Average training loss: {avg_train_loss:.4f}")
# 评估模型
val_metrics = evaluate_model(model, val_dataloader, device)
print(f"Validation Loss: {val_metrics['loss']:.4f}")
print(f"Validation Accuracy: {val_metrics['accuracy']:.4f}")
print(f"Validation F1 Score: {val_metrics['f1']:.4f}")
# 保存最佳模型
if val_metrics['f1'] > best_f1:
best_f1 = val_metrics['f1']
# 保存LoRA权重
model.save_pretrained("./best_weibo_sentiment_lora")
print("Saved best LoRA model!")
# 评估函数
def evaluate_model(model, dataloader, device):
model.eval()
total_loss = 0
all_preds = []
all_labels = []
with torch.no_grad():
for batch in tqdm(dataloader, desc="Evaluating"):
batch = {k: v.to(device) for k, v in batch.items()}
outputs = model(
input_ids=batch['input_ids'],
attention_mask=batch['attention_mask'],
labels=batch['labels']
)
loss = outputs.loss
total_loss += loss.item()
# 获取预测结果
logits = outputs.logits
preds = torch.argmax(logits, dim=1).cpu().numpy()
labels = batch['labels'].cpu().numpy()
all_preds.extend(preds)
all_labels.extend(labels)
# 计算评估指标
accuracy = accuracy_score(all_labels, all_preds)
f1 = f1_score(all_labels, all_preds, average='macro')
avg_loss = total_loss / len(dataloader)
return {
'loss': avg_loss,
'accuracy': accuracy,
'f1': f1
}
def main():
# 设置模型本地保存路径
model_name = 'uer/gpt2-chinese-cluecorpussmall'
local_model_path = './models/gpt2-chinese'
# 确保目录存在
os.makedirs(local_model_path, exist_ok=True)
os.makedirs('./best_weibo_sentiment_lora', exist_ok=True)
# 加载数据集
print("加载微博情感数据集...")
df = pd.read_csv('dataset/weibo_senti_100k.csv')
# 分割数据集
train_df, val_df = train_test_split(df, test_size=0.1, random_state=42, stratify=df['label'])
# 加载tokenizer
print("加载预训练模型和tokenizer...")
# 检查本地是否已有模型
if os.path.exists(os.path.join(local_model_path, 'config.json')):
print(f"从本地路径加载tokenizer: {local_model_path}")
tokenizer = BertTokenizer.from_pretrained(local_model_path)
else:
print(f"从Hugging Face下载tokenizer到: {local_model_path}")
tokenizer = BertTokenizer.from_pretrained(model_name, cache_dir=local_model_path)
# 保存tokenizer到本地
tokenizer.save_pretrained(local_model_path)
# 设置padding token
if tokenizer.pad_token is None:
tokenizer.pad_token = '[PAD]'
# 记录pad_token的ID
pad_token_id = tokenizer.pad_token_id
# 创建数据集
train_dataset = WeiboSentimentDataset(
train_df['review'].values,
train_df['label'].values,
tokenizer
)
val_dataset = WeiboSentimentDataset(
val_df['review'].values,
val_df['label'].values,
tokenizer
)
# 创建数据加载器
train_dataloader = DataLoader(train_dataset, batch_size=16, shuffle=True)
val_dataloader = DataLoader(val_dataset, batch_size=16)
# 设置设备
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
print(f"使用设备: {device}")
# 加载预训练的GPT2模型
print("加载GPT2模型...")
if (os.path.exists(os.path.join(local_model_path, 'pytorch_model.bin')) or
os.path.exists(os.path.join(local_model_path, 'model.safetensors'))):
print(f"从本地路径加载模型权重: {local_model_path}")
model = GPT2ForSequenceClassification.from_pretrained(local_model_path, num_labels=2)
else:
print(f"从Hugging Face下载模型权重到: {local_model_path}")
# 直接从Hugging Face下载并保存完整模型
model = GPT2ForSequenceClassification.from_pretrained(model_name, num_labels=2)
model.save_pretrained(local_model_path)
# 确保模型使用与tokenizer相同的pad_token_id
model.config.pad_token_id = pad_token_id
# 配置LoRA参数
print("配置LoRA参数...")
lora_config = LoraConfig(
task_type=TaskType.SEQ_CLS, # 序列分类任务
target_modules=["c_attn", "c_proj"], # GPT2的注意力投影层
inference_mode=False, # 训练模式
r=8, # LoRA秩,控制可训练参数数量
lora_alpha=32, # LoRA alpha参数,缩放因子
lora_dropout=0.1, # LoRA Dropout
)
# 将模型转换为PEFT格式的LoRA模型
print("创建LoRA模型...")
model = get_peft_model(model, lora_config)
model.print_trainable_parameters() # 打印可训练参数数量和占比
model.to(device)
# 设置优化器和学习率调度器
print("设置优化器...")
optimizer = AdamW(
model.parameters(), # PEFT会自动处理参数筛选
lr=5e-4, # LoRA通常使用较高的学习率
eps=1e-8
)
# 设置总训练步数和warmup步数
total_steps = len(train_dataloader) * 3 # 3个epoch
warmup_steps = int(total_steps * 0.1) # 10%的warmup
scheduler = get_linear_schedule_with_warmup(
optimizer,
num_warmup_steps=warmup_steps,
num_training_steps=total_steps
)
# 训练模型
print("开始训练...")
train_model(
model=model,
train_dataloader=train_dataloader,
val_dataloader=val_dataloader,
optimizer=optimizer,
scheduler=scheduler,
device=device,
epochs=3
)
print("训练完成!")
print("LoRA权重已保存到: ./best_weibo_sentiment_lora/")
if __name__ == "__main__":
main()