说到特征降维/选择的问题，大部分EDA的套路都是从model训练的loss来判断feature importance。其实有一个简单易行而且很有效的办法是在CV里面用做feature permutation，对原始特征shuffle得到shadow（也可以加一些噪音），在通过zscore比较两者差异来判断importance，不断遍历筛选。在ESLII中593页有提到这个办法。R里面有一个包Boruta可以做这件事，py也有：https://github.com/scikit-learn-contrib/boruta_py
BY Data Science Archive
You can’t. What you can do, though, is use WhatsApp’s and Telegram’s web platforms to transfer stickers. It’s easy, but might take a while.Open WhatsApp in your browser, find a sticker you like in a chat, and right-click on it to save it as an image. The file won’t be a picture, though—it’s a webpage and will have a .webp extension. Don’t be scared, this is the way. Repeat this step to save as many stickers as you want.Then, open Telegram in your browser and go into your Saved messages chat. Just as you’d share a file with a friend, click the Share file button on the bottom left of the chat window (it looks like a dog-eared paper), and select the .webp files you downloaded. Click Open and you’ll see your stickers in your Saved messages chat. This is now your sticker depository. To use them, forward them as you would a message from one chat to the other: by clicking or long-pressing on the sticker, and then choosing Forward.
Like a stock, you can buy and hold Bitcoin as an investment. You can even now do so in special retirement accounts called Bitcoin IRAs. No matter where you choose to hold your Bitcoin, people’s philosophies on how to invest it vary: Some buy and hold long term, some buy and aim to sell after a price rally, and others bet on its price decreasing. Bitcoin’s price over time has experienced big price swings, going as low as $5,165 and as high as $28,990 in 2020 alone. “I think in some places, people might be using Bitcoin to pay for things, but the truth is that it’s an asset that looks like it’s going to be increasing in value relatively quickly for some time,” Marquez says. “So why would you sell something that’s going to be worth so much more next year than it is today? The majority of people that hold it are long-term investors.”
Data Science Archive from jp