1. 引言
预测广告点击率(CTR)是在线广告系统中的一个关键任务。标题和图片是影响CTR的重要因素。以下教程将展示如何使用高级方法结合标题和图片特征来预测CTR。
2. 环境准备
首先,确保你已经安装了必要的Python库:
pip install pandas numpy scikit-learn xgboost transformers torch torchvision
3. 数据准备
假设你有一个包含广告标题、图片和点击数据的数据集,名为ad_data.csv。数据集的结构如下:
- 标题 (
title) - 图片路径 (
image_path) - 点击标签 (
clicked)
4. Python代码示例
以下代码示例展示了如何使用BERT和Swin Transformer结合标题和图片特征来预测CTR:
import pandas as pd
import torch
from transformers import BertTokenizer, BertModel
from torchvision import models, transforms
from torch.utils.data import Dataset, DataLoader
import torch.nn as nn
import torch.optim as optim
# 加载数据集
data = pd.read_csv('ad_data.csv')
# 定义数据集类
class AdDataset(Dataset):
def __init__(self, data, tokenizer, transform):
self.data = data
self.tokenizer = tokenizer
self.transform = transform
def __len__(self):
return len(self.data)
def __getitem__(self, idx):
title = self.data.iloc[idx, 0]
image_path = self.data.iloc[idx, 1]
clicked = self.data.iloc[idx, 2]
# 处理标题
inputs = self.tokenizer(title, return_tensors='pt', max_length=512, padding='max_length', truncation=True)
title_ids = inputs['input_ids'].squeeze()
attention_mask = inputs['attention_mask'].squeeze()
# 处理图片
image = Image.open(image_path)
image = self.transform(image)
image = image.unsqueeze(0)
return {
'title_ids': title_ids,
'attention_mask': attention_mask,
'image': image,
'clicked': torch.tensor(clicked, dtype=torch.long)
}
# 初始化BERT和Swin模型
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
transform = transforms.Compose([
transforms.Resize((224, 224)),
transforms.ToTensor(),
transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225])
])
bert_model = BertModel.from_pretrained('bert-base-uncased')
swin_model = models.swin_bert_tiny(weights='IMAGENET1K_V1')
# 定义自定义模型
class AdModel(nn.Module):
def __init__(self):
super(AdModel, self).__init__()
self.bert = bert_model
self.swin = swin_model
self.dropout = nn.Dropout(0.1)
self.fc = nn.Linear(768 + 768, 2)
def forward(self, title_ids, attention_mask, image):
title_features = self.bert(title_ids, attention_mask=attention_mask).pooler_output
image_features = self.swin(image).flatten()
combined_features = torch.cat((title_features, image_features), dim=1)
output = self.dropout(combined_features)
output = self.fc(output)
return output
# 初始化数据集和数据加载器
dataset = AdDataset(data, tokenizer, transform)
batch_size = 32
data_loader = DataLoader(dataset, batch_size=batch_size, shuffle=True)
# 训练模型
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model = AdModel().to(device)
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(model.parameters(), lr=1e-5)
for epoch in range(5):
model.train()
total_loss = 0
for batch in data_loader:
title_ids = batch['title_ids'].to(device)
attention_mask = batch['attention_mask'].to(device)
image = batch['image'].to(device)
clicked = batch['clicked'].to(device)
optimizer.zero_grad()
outputs = model(title_ids, attention_mask, image)
loss = criterion(outputs, clicked)
loss.backward()
optimizer.step()
total_loss += loss.item()
print(f'Epoch {epoch+1}, Loss: {total_loss / len(data_loader)}')
# 评估模型
model.eval()
with torch.no_grad():
total_correct = 0
for batch in data_loader:
title_ids = batch['title_ids'].to(device)
attention_mask = batch['attention_mask'].to(device)
image = batch['image'].to(device)
clicked = batch['clicked'].to(device)
outputs = model(title_ids, attention_mask, image)
_, predicted = torch.max(outputs, dim=1)
total_correct += (predicted == clicked).sum().item()
accuracy = total_correct / len(data)
print(f'Test Accuracy: {accuracy:.4f}')
5. 总结
通过结合BERT和Swin Transformer处理标题和图片特征,可以显著提高CTR预测的准确性。这种方法利用多模态特征融合技术,能够更好地捕捉用户的偏好和行为。
案例示例
- CTR驱动的广告图像生成:利用多模态大语言模型生成CTR优化的广告图像,可以提高广告的点击率
- 深度CTR预测模型:使用深度神经网络直接从原始图像像素和其他特征预测CTR,提高了预测的准确性