603 reputation
8
bio website ventirisk.com
location State College, PA
age 47
visits member for 5 months
seen Apr 9 at 1:48
stats profile views 60

Arthur Small is co-founder and CEO of Venti Risk Management, a consultancy and software development firm based in State College, Pennsylvania, USA. His work focuses on the management of risks arising due to variations in weather and climate.

Before co-founding Venti, Small served as Associate Professor of Applied Economics and Finance in the Department of Meteorology at Penn State University; and as Assistant Professor in the Graduate School of Business and the School of International and Public Affairs at Columbia University. He holds a A.B. degree in mathematics from Columbia University, an M.S. in mathematics from Cornell University, and a Ph.D. in Agricultural and Resource Economics from the University of California at Berkeley.


Mar
24
comment Is a subset $B= {(-\infty,t),t\in \mathbb{R} }$ an event of sample space $\mathbb{R}$?
@Zen is correct, and I was mistaken. I have edited my answer accordingly.
Mar
24
revised Is a subset $B= {(-\infty,t),t\in \mathbb{R} }$ an event of sample space $\mathbb{R}$?
Amended answer to correct an error identified by another user; fixed grammar.
Mar
23
answered Is a subset $B= {(-\infty,t),t\in \mathbb{R} }$ an event of sample space $\mathbb{R}$?
Feb
3
answered Creating conditional probability distribution
Jan
30
comment Determine likelihood that a list of N items contains no negative results after examining X items
For an answer to a question that is formally similar to yours, see: stats.stackexchange.com/questions/47286/…
Jan
20
comment Measuring representativeness of a (non-random) selection
@Thilo: Oh, dear. I suppose I invited that follow-up, so have only myself to blame. Answering would, alas, take a long while. 'Any' stats textbook will cover the topic: see, e.g., W.H. Greene, Econometric Analysis. On 'why not?', I'll recommend a book I find canonical that covers the philosophical and practical problems of hypothesis testing quite well and in depth: Statistical Decision Theory and Bayesian Analysis by J.O. Berger, amazon.com/gp/product/1441930744. Very short answer: I'm interested in using stats to make better decisions under uncertainty. HT doesn't help.
Jan
17
comment Measuring representativeness of a (non-random) selection
There is a noteworthy economic literature on statistical measurement of race and sex discrimination in, e.g., labor markets, that might be useful. A seminal work is: The Statistical Theory of Racism and Sexism Edmund S. Phelps The American Economic Review Vol. 62, No. 4 (Sep., 1972), pp. 659-661 Published by: American Economic Association Article Stable URL: jstor.org/stable/1806107
Jan
17
revised Measuring representativeness of a (non-random) selection
In example: Replaced hand-waving approximate odds ratio with exact calculation; added brief proviso about election procedures for U.S. senators.
Jan
17
revised Measuring representativeness of a (non-random) selection
Added interpretation of the numerical result as an odds ratio.
Jan
17
answered Measuring representativeness of a (non-random) selection
Jan
16
comment Minimizing variance of an estimator under sampling cost penalty
@StasK: Touche$'$ :)
Jan
16
awarded  Tag Editor
Jan
16
revised value-of-information wiki excerpt
added 138 characters in body
Jan
16
wiki created value-of-information excerpt
Jan
16
suggested suggested edit on value-of-information tag wiki excerpt
Jan
16
comment Timeseries stationarity
Differencing is most useful for analyzing series with unit roots, e.g., AR processes with coefficients equal to (or close to) unity. Consider the simplest such case in which $y_t$ follows a random walk, i.e., in which $y_t = y_{t-1} + e_t$. This process is non-stationary. However, the differenced series is stationary. Ref: en.wikipedia.org/wiki/Unit_root
Jan
16
revised Minimizing variance of an estimator under sampling cost penalty
Fixed statement of an equation.
Jan
16
comment Minimizing variance of an estimator under sampling cost penalty
@Jugurtha: My bad: I should have written $E[C \mid \cdot]$ as a double integral: $E[C \mid \cdot] = \int \int C(\hat{\theta},\theta) f(\hat{\theta} \mid x_{1:n}) d\hat{\theta} f({\theta} \mid x_{1:n}) d\theta$. That is, given a beliefs about the distribution of $\theta$, you are able to formulate expectations of how far off a given point estimate is likely to be. (I'll edit my original answer to fix.)
Jan
16
comment R vs SAS, why is SAS prefered by private companies?
@DimitriyV.Masterov: Revolution R is a commercial "enterprise" version of R that claims to allow R to run in-database. (I have not reviewed or audited this claim.) Revo R is not free ($1,000, I think), but its much cheaper than SAS.
Jan
15
revised Minimizing variance of an estimator under sampling cost penalty
Fixed typo (had too many "nots")