1. 数据收集与预处理
- 数据清洗:处理缺失值、异常值等。
- 特征工程:提取有助于预测的特征。
- 数据标准化:将时间序列数据标准化,使其具有零均值和单位方差,有助于模型训练。
- 滑动窗口划分:将时间序列数据划分为多个滑动窗口,每个窗口包含15个历史时间点的数据值,用于预测下一个时间点的值。
- 数据集中部分数据如下:
0.491920000000000 0.493110000000000 0.493500000000000 0.493130000000000 0.493030000000000 0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000
0.493110000000000 0.493500000000000 0.493130000000000 0.493030000000000 0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000
0.493500000000000 0.493130000000000 0.493030000000000 0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000
0.493130000000000 0.493030000000000 0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000
0.493030000000000 0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000
0.493300000000000 0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000
0.494200000000000 0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000
0.493710000000000 0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000
0.496820000000000 0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000
0.517990000000000 0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000
0.520820000000000 0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000 0.560570000000000
0.519940000000000 0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000 0.560570000000000 0.558160000000000
0.526180000000000 0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000 0.560570000000000 0.558160000000000 0.561030000000000
0.539890000000000 0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000 0.560570000000000 0.558160000000000 0.561030000000000 0.561560000000000
0.539940000000000 0.544180000000000 0.546260000000000 0.548060000000000 0.546630000000000 0.555100000000000 0.563040000000000 0.579750000000000 0.565900000000000 0.563570000000000 0.564210000000000 0.560570000000000 0.558160000000000 0.561030000000000 0.561560000000000 0.560440000000000
2. 设计BiLSTM神经网络模型
使用MATLAB的深度学习工具箱,构建BiLSTM神经网络模型。需要指定模型的层数、每层神经元的数量、激活函数等超参数。
可以使用bilstmLayer来创建双向LSTM层,这是学习双向长期依赖关系的RNN层。
3. 编译模型
- 选择损失函数:对于回归问题,通常使用均方误差(MSE)作为损失函数。
- 选择优化器:常用的优化器包括Adam、SGD等。
- 选择评估指标:常用的评估指标包括均方根误差(RMSE)。
4. 训练模型
- 划分数据集:将数据集划分为训练集、验证集和测试集。
- 模型训练:使用训练集数据训练模型,并在验证集上进行模型评估,以防止过拟合。
- 超参数调优:调整模型的超参数,如学习率等,以获得更好的性能。
5. 模型评估与测试
- 评估模型:在测试集上评估模型的性能,使用RMSE等指标。
- 结果分析:分析模型预测结果与实际值之间的差异,评估模型的准确性和泛化能力。
6. 部分MATLAB示例
%% 绘图
figure
plot(1: M, T_train, 'r-*', 1: M, T_sim1, 'b-o', 'LineWidth', 1)
legend('真实值', '预测值')
xlabel('预测样本')
ylabel('预测结果')
string = {'训练集预测结果对比'; ['RMSE=' num2str(error1)]};
title(string)
xlim([1, M])
gridfigure
plot(1: N, T_test, 'r-*', 1: N, T_sim2, 'b-o', 'LineWidth', 1)
legend('真实值', '预测值')
xlabel('预测样本')
ylabel('预测结果')
string = {'测试集预测结果对比'; ['RMSE=' num2str(error2)]};
title(string)
xlim([1, N])
grid
figure
scatter(T_train, T_sim1, sz, c)
hold on
plot(xlim, ylim, '--k')
xlabel('训练集真实值');
ylabel('训练集预测值');
xlim([min(T_train) max(T_train)])
ylim([min(T_sim1) max(T_sim1)])
title('训练集预测值 vs. 训练集真实值')figure
scatter(T_test, T_sim2, sz, c)
hold on
plot(xlim, ylim, '--k')
xlabel('测试集真实值');
ylabel('测试集预测值');
xlim([min(T_test) max(T_test)])
ylim([min(T_sim2) max(T_sim2)])
title('测试集预测值 vs. 测试集真实值')