问题
What does the background in blue mean or determine in the regression plot when using seaborn? What determines its width at both ends?
回答1:
According to seaborn documentation, that area rappresents the confidence interval. You can set it through the ci parameter:
Size of the confidence interval for the regression estimate. This will be drawn using translucent bands around the regression line. The confidence interval is estimated using a bootstrap; for large datasets, it may be advisable to avoid that computation by setting this parameter to None
For the statistical meaning of confidence interval, I suggest you the wikipedia definition:
The confidence interval represents values for the population parameter for which the difference between the parameter and the observed estimate is not statistically significant at the 10% level
Strictly speaking, there is 95% of probability (seaborn uses 95% as default value) that a new sample falls in the confidence interval. In practice, the confidence interval indicates the forecast error associated with data dispersion.
来源：https://stackoverflow.com/questions/62167783/what-does-the-background-area-mean-in-seaborn-regression-plot