作者aaasdf (ㄎㄎ)
看板Economics
标题[请益] 凹性与凸性
时间Tue Oct 16 20:19:56 2007
若Hessian为N.D(负定) , 则表示此为convex or concave?
若Hessian为P.D(正定) , 则表示此为convex or concave?
一个函数为convex or concave 可用Hessian来判断吗? Why?
找不到相关的说明
谢谢指教!!
补问一个问题...
为什麽convex = concave function?
而 concave= convex function?
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◆ From: 59.121.3.213
※ 编辑: aaasdf 来自: 59.121.3.213 (10/16 20:20)
1F：推 DarthRaider:可以找找经数或金数教科书 121.13.42.89 10/16 22:37
※ 编辑: aaasdf 来自: 59.121.3.213 (10/17 22:56)
3F：推 aaasdf:为什麽convex = concave function? 59.121.3.213 10/17 22:56
4F：推 akai0928:最後的问题在於~set与function之间140.134.110.252 10/17 22:59
5F：→ akai0928:找一下书吧~convex set,concave function140.134.110.252 10/17 23:00
6F：→ akai0928:这些名词之间的关系140.134.110.252 10/17 23:01
7F：推 beatitude:高微的书中有证明 61.216.204.55 10/18 01:32
8F：推 liuwanju:f"(.)<0 <==> N.D. 59.104.190.122 10/18 23:49
9F：→ liuwanju:f"(.)>0 <==>P.D. 59.104.190.122 10/18 23:52
10F：→ liuwanju:f"(.)<0 : Strictly Concave. 59.104.190.122 10/18 23:53
11F：→ liuwanju:f"(.)>0 :Strictly Convex. 59.104.190.122 10/18 23:54
12F：→ liuwanju:f"(.)>0 <==> P.D.is Convex. 59.104.190.122 10/18 23:56