{"version":"https://jsonfeed.org/version/1.1","title":"苏迟但到的主页","home_page_url":"https://kexohproject.pages.dev","feed_url":"https://kexohproject.pages.dev/json/","description":"<p>你好，欢迎访问个人主页！</p><p>擅长密码学，安全分析，数字水印等技术。</p><p>你可以联系我通过:findmykexin@gmail.com或者知乎私信。</p><p>我的知乎链接：<a href=\"https://www.zhihu.com/people/su-chi-dan-dao\" rel=\"noopener noreferrer\" target=\"_blank\">苏迟但到 - 知乎 (zhihu.com)</a></p><p>我的github链接：<a href=\"https://github.com/kexinoh\" rel=\"noopener noreferrer\" target=\"_blank\">kexinoh</a></p>","icon":"https://kexohcdn.gptapi.cyou/kexohproject/production/images/channel-2e54d141ee195646ca12a9d16507a908.jpg","favicon":"https://kexohcdn.gptapi.cyou/kexohproject/production/images/favicon-340a2925d02a0386f3b954a032834917.jpg","authors":[{"name":"苏迟但到"}],"language":"zh-cn","items":[{"id":"mevesCn6qkR","title":"一个数从1开始，每次各有50%的概率乘0.9或者乘1.1，重复足够多的次数以后，情况会如何？","content_html":"<p data-pid=\"kBPU-r_F\">期望是1。</p><p data-pid=\"SYnNMag1\">这个证明很简单（使用初中知识），如下</p><p data-pid=\"YLU7sEEd\">1.当第一次时，期望是1。</p><p data-pid=\"JfFWt909\">2.假设第n次的期望为1。</p><p data-pid=\"wTe9H6fO\">3.下证第n+1次的期望也为1。</p><p data-pid=\"u_4FuYUS\">对于任意第n次的期望项x和它的概率p,都有50%变为[1.1x，0.5p]和[0.9x,0.5p]。</p><p data-pid=\"gTO3t6vr\">因此对于任意的第n次的期望项，到下一轮的期望项对应的期望值不会改变。因此总体的期望值不会改变。</p><p></p>","content_text":"期望是1。\n\n这个证明很简单（使用初中知识），如下\n\n1.当第一次时，期望是1。\n\n2.假设第n次的期望为1。\n\n3.下证第n+1次的期望也为1。\n\n对于任意第n次的期望项x和它的概率p,都有50%变为[1.1x，0.5p]和[0.9x,0.5p]。\n\n因此对于任意的第n次的期望项，到下一轮的期望项对应的期望值不会改变。因此总体的期望值不会改变。\n\n","date_published":"2023-07-08T04:29:57.000Z","_microfeed":{"web_url":"https://kexohproject.pages.dev/i/150percent0911-mevesCn6qkR/","json_url":"https://kexohproject.pages.dev/i/mevesCn6qkR/json/","rss_url":"https://kexohproject.pages.dev/i/mevesCn6qkR/rss/","guid":"mevesCn6qkR","status":"published","itunes:title":"New Article Title for iTunes","date_published_short":"Sat Jul 08 2023","date_published_ms":1688790597000}}],"_microfeed":{"microfeed_version":"0.1.2","base_url":"https://kexohproject.pages.dev","categories":[{"name":"Education","categories":[{"name":"Language Learning"}]},{"name":"Technology"}],"subscribe_methods":[{"name":"RSS","type":"rss","url":"https://kexohproject.pages.dev/rss/","image":"https://kexohproject.pages.dev/assets/brands/subscribe/rss.png","enabled":true,"editable":false,"id":"4KlfbtkEfzy"},{"name":"JSON","type":"json","url":"https://kexohproject.pages.dev/json/","image":"https://kexohproject.pages.dev/assets/brands/subscribe/json.png","enabled":true,"editable":false,"id":"DVFm7TYiNSq"}],"description_text":"你好，欢迎访问个人主页！\n\n擅长密码学，安全分析，数字水印等技术。\n\n你可以联系我通过:findmykexin@gmail.com或者知乎私信。\n\n我的知乎链接：苏迟但到 - 知乎 (zhihu.com)\n\n我的github链接：kexinoh","copyright":"©2024","itunes:type":"episodic","items_sort_order":"newest_first"}}