Understanding the Fundamental Shift in Search Behavior
Give them a free ebook and host it on a landing page where they have to enter the email to download the file and also create a forum page on your website, asks your visitors what questions they might have about your business, and collects email addresses to follow up with them.，推荐阅读im钱包官方下载获取更多信息
优点：输出在 (−1,1)，比 sigmoid 居中，对梯度更友好，这一点在WPS官方版本下载中也有详细论述
Глеб Макаревичсотрудник Центра Индоокеанского региона ИМЭМО РАН，更多细节参见同城约会