處理非定態性
在這個練習中,你會再次視覺化模型分數的變動,但這次面對的是隨時間改變統計特性的資料。
model 中已經存有一個 Linear regression 模型物件,cv 是交叉驗證物件,資料則在 X 和 y。
本練習屬於課程
Python 的時間序列資料機器學習
動手互動練習
試著完成這個範例程式碼,體驗一下這個練習。
# Pre-initialize window sizes
window_sizes = [25, 50, 75, 100]
# Create an empty DataFrame to collect the stores
all_scores = ____(index=times_scores)
# Generate scores for each split to see how the model performs over time
for window in window_sizes:
# Create cross-validation object using a limited lookback window
cv = ____(n_splits=100, max_train_size=window)
# Calculate scores across all CV splits and collect them in a DataFrame
this_scores = ____(____, ____, ____, cv=cv, scoring=my_pearsonr)
all_scores['Length {}'.format(window)] = this_scores