电商数据建模
一、分析背景与目的
1.1 背景介绍
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| 电商平台数据分析是最为典型的一个数据分析赛道,且电商数据分析有着比较成熟的数据分析模型,比如:人货场模型。此文中我将通过分析国内最大的电商平台------淘宝的用户行为,来巩固数据分析技能以及思维。通过分析用户行为,以此来实现精准营销,总结现有问题,获得业务增长 |
1.2 数据说明
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| 该数据包含了20230523用户一天购物行为的所有数据,主要包括人货场三个维度信息。用户维度、商品维度、地区维度构成一个用户下单的行为事实表。 |
1.3数据分析流程
提出业务问题---确认粒度---数据处理和清洗---构建模型---数据可视化------根据数据可视化分析解决问题
业务问题:
1.如何提高品牌销售力度?
2.如何刺激地区市场消费潜力?
3.如何刺激用户消费?
4.如何减少产品成本?
确认粒度:
用户信息表、订单表、订单明细表
商品信息表、品牌信息表、一二三级分类信息表
省份信息表、地区信息表
核心算法代码分享如下:
python
import sys
import numpy as np
from torch.utils.data import DataLoader
from torch import nn
import torch.nn.functional as F
import torch
from sklearn.metrics import precision_score,recall_score,accuracy_score
import dataloader
class ALS_MLP (nn.Module):
def __init__(self, n_users, n_items, dim):
super(ALS_MLP, self).__init__()
'''
:param n_users: 用户数量
:param n_items: 物品数量
:param dim: 向量维度
'''
# 随机初始化用户的向量,
self.users = nn.Embedding( n_users, dim, max_norm=1 )
# 随机初始化物品的向量
self.items = nn.Embedding( n_items, dim, max_norm=1 )
#初始化用户向量的隐层
self.u_hidden_layer1 = self.dense_layer(dim, dim // 2)
self.u_hidden_layer2 = self.dense_layer(dim//2, dim // 4)
#初始化物品向量的隐层
self.i_hidden_layer1 = self.dense_layer(dim, dim // 2)
self.i_hidden_layer2 = self.dense_layer(dim//2, dim // 4)
self.sigmoid = nn.Sigmoid()
def dense_layer(self,in_features,out_features):
#每一个mlp单元包含一个线性层和激活层,当前代码中激活层采取Tanh双曲正切函数。
return nn.Sequential(
nn.Linear(in_features, out_features),
nn.Tanh()
)
def forward(self, u, v, isTrain=True):
'''
:param u: 用户索引id shape:[batch_size]
:param i: 用户索引id shape:[batch_size]
:return: 用户向量与物品向量的内积 shape:[batch_size]
'''
u = self.users(u)
v = self.items(v)
u = self.u_hidden_layer1(u)
u = self.u_hidden_layer2(u)
v = self.i_hidden_layer1(v)
v = self.i_hidden_layer2(v)
#训练时采取dropout来防止过拟合
if isTrain:
u = F.dropout(u)
v = F.dropout(v)
uv = torch.sum( u*v, axis = 1)
logit = self.sigmoid(uv*3)
return logit
def doEva(net, d):
d = torch.LongTensor(d)
u, i, r = d[:, 0], d[:, 1], d[:, 2]
with torch.no_grad():
out = net(u,i,False)
y_pred = np.array([1 if i >= 0.5 else 0 for i in out])
y_true = r.detach().numpy()
p = precision_score(y_true, y_pred)
r = recall_score(y_true, y_pred)
acc = accuracy_score(y_true,y_pred)
return p,r,acc
def train( epochs = 10, batchSize = 1024, lr = 0.001, dim = 256, eva_per_epochs = 1):
'''
:param epochs: 迭代次数
:param batchSize: 一批次的数量
:param lr: 学习率
:param dim: 用户物品向量的维度
:param eva_per_epochs: 设定每几次进行一次验证
'''
#读取数据
user_set, item_set, train_set, test_set = \
dataloader.readRecData(test_ratio = 0.1)
#初始化ALS模型
net = ALS_MLP(len(user_set), len(item_set), dim)
#定义优化器
optimizer = torch.optim.AdamW( net.parameters(), lr = lr, weight_decay=0.2)
#定义损失函数
criterion = torch.nn.BCELoss()
#开始迭代
for e in range(epochs):
all_lose = 0
#每一批次地读取数据
for u, i, r in DataLoader(train_set,batch_size = batchSize, shuffle = True):
optimizer.zero_grad()
r = torch.FloatTensor(r.detach().numpy())
result = net(u,i)
loss = criterion(result,r)
all_lose += loss
loss.backward()
optimizer.step()
print('epoch {}, avg_loss = {:.4f}'.format(e,all_lose/(len(train_set)//batchSize)))
#评估模型
if e % eva_per_epochs==0:
p, r, acc = doEva(net, train_set)
print('train: Precision {:.4f} | Recall {:.4f} | accuracy {:.4f}'.format(p, r, acc))
p, r, acc = doEva(net, test_set)
print('test: Precision {:.4f} | Recall {:.4f} | accuracy {:.4f}'.format(p, r, acc))
def als_mlp_predict(userId=1, itemSize=100, count=4, dim=64):
# 读取数据
user_set, item_set, train_set, test_set = \
dataloader.readRecData( test_ratio=0.1)
# 预测一个用户的所有的评分形成一个元祖
train_set = []
for i in range(1, itemSize):
train_set.append((userId, i, 0))
# print(train_set)
# print(train_set)
# 初始化ALS模型
net = ALS_MLP(len(user_set), len(item_set), dim)
d = torch.LongTensor(train_set)
u, i, r = d[:, 0], d[:, 1], d[:, 2]
with torch.no_grad():
out = net(u, i)
predict = []
preds = out.tolist()
# print(len(preds))
# 找出最大值,通过这种方式可以求出多个
for i in range(0, count):
m = max(preds)
idx = preds.index(m)
predict.append(dict(iid=idx, score=m))
del preds[idx]
# print(predict)
return predict
def test(dim = 64):
result = als_mlp_predict(1, 2000, 5)
print(result)
if __name__ == '__main__':
# train()
# test()
param1 = sys.argv[1]
# param1 = "1"
result = als_mlp_predict(int(param1), 55, 4)
list = []
# print(result)
for r in result:
list.append(dict(iid=r['iid'], rate=r['score']))
print(list)