8,681 reputation
21838
bio website gottwurfelt.wordpress.com
location San Francisco, CA
age 30
visits member for 4 years, 1 month
seen 9 hours ago

Quantitative analyst and math blogger.


1d
reviewed Reject suggested edit on How to find the remainder when the following series is divided by 12?
Aug
15
comment Is there a name for the function $\max(x, 0)$?
It should be noted that the negative part is, in fact, a positive number. For example the negative part of -3 is 3.
Aug
11
reviewed Approve suggested edit on optimization tag wiki
Aug
5
comment Asymptotic behavior of $\sum\limits_{k=1}^n \frac{2^k}{k}$
Call your sum $S_n$. Let $T_n = S_n/2^n$; then it's not hard to show that $T_1 = 1$, $T_n = T_{n-1}/2 + 1/n$. You want to show $T_n \sim 2/(n+1)$. Not sure this helps.
Aug
5
awarded  Good Answer
Jul
21
awarded  Yearling
Jul
17
reviewed Approve suggested edit on A strange puzzle having two possible solutions
Jul
16
comment Probability of Random Variable Minus Random Variable
There are quantitative bounds on the approximation such as the Berry-Esseen inequality, but those are almost surely beyond the scope of the course the poster is taking.
Jul
7
awarded  Nice Answer
Jun
18
reviewed Edit suggested edit on Applications of groups, rings and modules in life
Jun
18
revised Applications of groups, rings and modules in life
formatting, capitals
Jun
1
awarded  Necromancer
May
20
answered How to find the sum: $1^{\frac{1}{3}}+2^{\frac{1}{3}}+3^{\frac{1}{3}}+ . . . +(50)^{\frac{1}{3}}$
May
15
comment Probability of getting better than a certain score
Andre, you can always just run a more involved simulation (more trials, or compute some other intermediate results) if you want a coffee break.
May
9
comment How prove this frog can finite steps jump the point $(\frac{1}{5},\frac{1}{17})$
If I understand the problem correctly, a jump like (1/17, 4/17) isn't allowed since it's not of length 1. But you could use (8/17, 15/17) in this context.
Mar
29
answered Two people A and B throwing dice
Mar
22
reviewed Approve suggested edit on derivation of simple linear regression parameters
Mar
19
awarded  combinatorics
Mar
14
comment How likely is it not to be anyone's best friend?
I wonder what, say, Facebook's data on this would look like, where "best friend" would be defined as "person most interacted with on Facebook". Of course this has nothing to do with your model.
Feb
27
reviewed Edit suggested edit on For all sets A, B and C, if $A\setminus(B \cup C) = \emptyset$ ; then $A\setminus C\subseteq B$.