Jun 24, 2019 · 图像以上为 凸集 的就是凸函数，如开口向上的二次函数，英文里叫Convex或concave up，反过来就是凹函数，英文叫Concave或concave down，这是国际上的定义。 国内大部分经济学 …

英文世界中，一般分为Convex Function和Concave Function 通常意义上，前面是向下凹，后面是向上凹。 一个 助记 是con后面跟的是V，形状就和V类似。 否则，则形状就是倒着的 Λ 而国内汉语世界， …

Nov 26, 2018 · How do I show that if a function satisfies f(αx + (1 − α)y)> αf(x) + (1 − α)f(y) with 0 <α <1, it is true that (assuming it exists) the second derivative f ″ (x) <0. I can see this is true visually in a …

那么我们来讲凸函数（convex function）为什么叫做是凸（convex）的： 这是因为凸函数与凸集（convex set）有联系，而凸集的定义没有争议。 1. 凸函数与凸集通过 sublevel sets 这个概念联系起 …

If you know the standard English meaning of the words convex and concave, you can remember that for a convex function it is the epigraph that is convex, and for a concave function it is the epigraph that is …

Functions whose negative is convex occur frequently and "concave [function]" came into use as a convenient description of this situation. The linguistic logic was clear enough to make this …

Convex function Quasiconvex function Pseudoconvex function 在R上考虑就很容易理解。在凸要求不高过xy连线的地方，拟凸只要求不高过xy中较大者，所以凸蕴含拟凸；而伪凸则要求，“切线”“指哪”函 …

Oct 21, 2019 · A line is concave, but not strictly concave. Consequently, the graph of a concave function can include linear segments, but the graph of a strictly concave function cannot contain a linear …

凸函数凹函数的中英文定义倒置？ 凸函数的英文是concave function；凹函数的英文是convex function...但是其实concave的英文翻译是凹，convex的… 显示全部 关注者 6 被浏览

Jan 26, 2017 · I am trying to understand concave functions, for which wikipedia gives an expression written as: now I am confused as how to understand this as the line over there says that this …