Profile

Cover photo
John Mount
Works at Win-Vector LLC
156,317 views
AboutPostsPhotosVideos+1's

Stream

John Mount

Shared publicly  - 
 
New Win-Vector LLC technical article: "Efficient accumulation in R"
http://blog.revolutionanalytics.com/2015/07/efficient-accumulation-in-r.html
by John Mount Data Scientist, Win-Vector LLC R has a number of very good packages for manipulating and aggregating data (plyr, sqldf, RevoScaleR, data.table, and more), but when it comes to accumulating results the beginning R user is often at sea. The R execution model is a bit exotic so many R users are very uncertain which methods of accumulating results are efficient and which are inefficient. Accumulating wheat (Photo: Cyron Ray Macey, some ...
1
John Mount's profile photo
 
Update: data.table is totally the way to go.

John Mount

Shared publicly  - 
 
Nina Zumel's next Win-Vector LLC technical article: Working with sessionized data 2: variable selection http://www.win-vector.com/blog/2015/07/working-with-sessionized-data-2-variable-selection/
In our previous post in this series, we introduced sessionization, or converting log data into a form that's suitable for analysis. We looked at basic considerations, like dealing with time, choosi...
1

John Mount

Shared publicly  - 
 
Today's one minute hate: OSX "my god its full of meh" https://www.youtube.com/watch?v=okmJ7IESJe8
1

John Mount

Shared publicly  - 
 
New Win-Vector LLC technical finance article
What is a good Sharpe ratio?
http://www.win-vector.com/blog/2015/06/what-is-a-good-sharpe-ratio/
We have previously written that we like the investment performance summary called the Sharpe ratio (though it does have some limits). What the Sharpe ratio does is: give you a dimensionless score t...
1

John Mount

Shared publicly  - 
 
Neural net image salad again (with code)
http://www.win-vector.com/blog/2015/06/neural-net-image-salad-again-with-code/  (with Michael Witbrock and Scott Neal Reilly, plus a call-out to Scott Draves).
Alexander Mordvintsev, Christopher Olah, and Mike Tyka, recently posted a great research blog article where they tried to visualize what a image classification neural net “wants to see.” They achieve this by optimizing the input to correspond to a fixed pattern of neural net internal node ...
1
In his circles
125 people

John Mount

Shared publicly  - 
Modern text encoding is a convoluted mess where costs can easily exceed benefits. I admit we are in a world that has moved beyond ASCII (which at best served only English, and even then without ful...
1
Brian Slesinsky's profile photoNir Yeffet's profile photoJohn Mount's profile photo
5 comments
 
Gotcha.

John Mount

Shared publicly  - 
 
Anyone remember the correct text and source of this almost remembered maxim? "Laws/axioms/rule that are true are true in the extreme.”  It is the mathematical idea that if a rule is correct than it is correct in all cases (even the cases that seem ridiculously hard).
1

John Mount

Shared publicly  - 
 
New Win-Vector LLC technical article by Nina Zumel: "Working with Sessionized Data 1: Evaluating Hazard Models" http://www.win-vector.com/blog/2015/07/working-with-sessionized-data-1-evaluating-hazard-models/
When we teach data science we emphasize the data scientist's responsibility to transform available data from multiple systems of record into a wide or denormalized form. In such a “ready to analyze...
1

John Mount

Shared publicly  - 
by John Mount Ph. D. Data Scientist at Win-Vector LLC Win-Vector's last article on A/B testing described the scope of the realistic circumstances of A/B testing in practice and gave links to different standard solutions. In this article we will be take an idealized specific situation allowing us to show a particularly beautiful solution to one very special type of A/B test. For this article we are assigning two different advertising message to ou...
1

John Mount

Shared publicly  - 
Win-Vector LLC is a consultancy founded in 2007 that specializes in research, algorithms, data-science, and training. (The name is an attempt at a mathematical pun.) Win-Vector LLC can complete your high value project quickly (some examples), and train your data science team to work much more ...
1

John Mount

Shared publicly  - 
John Mount Ph. D. Data Scientist at Win-Vector LLC An A/B test is a very simple controlled experiment where one group is subject to a new treatment (often group "B") and the other group (often group "A") is considered a control group. The classic example is attempting to compare defect rates of two production processes (the current process, and perhaps a new machine). Illustration: Boris Artzybasheff (photo James Vaughan, some rights reserved) In...
1
People
In his circles
125 people
Work
Occupation
Principal Consultant, Win-Vector LLC
Employment
  • Win-Vector LLC
    Principal Consultant, present
Story
Introduction
I produce applied research, prototyping and training in information extraction, algorithms and data-mining for web-scale businesses, hedge funds and start ups. Right now I do this as a consultant at Win-Vector LLC. 

Please check out our book Practical Data Science with R  http://www.manning.com/zumel/ http://www.amazon.com/Practical-Data-Science-With-R/dp/1617291560

Also check out the Win-Vector LLC blog http://www.win-vector.com/blog/ our Twitter feed https://twitter.com/WinVectorLLC .
Basic Information
Gender
Male
John Mount's +1's are the things they like, agree with, or want to recommend.
A dynamic programming solution to A/B test design | StatsBlogs.com | All...
www.statsblogs.com

(This article was originally published at Win-Vector Blog » Statistics, and syndicated at StatsBlogs.) Our last article on A/B testing descr

Estimating Generalization Error with the PRESS statistic
www.r-bloggers.com

As we’ve mentioned on previous occasions, one of the defining characteristics of data science is the emphasis on the availability of “large”

Factors are not first-class citizens in R
www.r-bloggers.com

The primary user-facing data types in the R statistical computing environment behave as vectors. That is: one dimensional arrays of scalar v

Frequentist inference only seems easy
www.r-bloggers.com

Two of the most common methods of statistical inference are frequentism and Bayesianism (see Bayesian and Frequentist Approaches: Ask the Ri

R style tip: prefer functions that return data frames
www.r-bloggers.com

While following up on Nina Zumel’s excellent Trimming the Fat from glm() Models in R I got to thinking about code style in R. And I realized

Trimming the Fat from glm() Models in R
www.r-bloggers.com

One of the attractive aspects of logistic regression models (and linear models in general) is their compactness: the size of the model grows

Save 45% on Practical Data Science with R (expires May 21, 2013)
www.r-bloggers.com

Please share this generous deal from Manning publications: save 45% on Practical Data Science with R through May 21, 2014. Please tweet, for

R has some sharp corners
www.r-bloggers.com

R is definitely our first choice go-to analysis system. In our opinion you really shouldn’t use something else until you have an articulated

Some R Resources for GLMs
www.r-bloggers.com

by Joseph Rickert Generalized Linear Models have become part of the fabric of modern statistics, and logistic regression, at least, is a “go

You don’t need to understand pointers to program using R
www.r-bloggers.com

R is a statistical analysis package based on writing short scripts or programs (versus being based on GUIs like spreadsheets or directed wor

Oldies but Goldies: Statistical Graphics Books
www.r-bloggers.com

I just wanted to plug for three classical books on statistical graphics that I really enjoyed reading. The books are old (that is, older tha

I can haz buzzwords?
biasedestimates.blogspot.com

Catty title aside, this post takes a good swing at defining terms we hear thrown around about data these days and they mostly do a good job.

Practical Data Science with R October 2013 update
www.r-bloggers.com

A quick status update on our upcoming book “Practical Data Science with R” by Nina Zumel and John Mount. We are really happy with how the bo

[Book] Practical Data Science with R
www.analyticbridge.com

Nina Zumel and John Mount have been working very hard on producing an exciting new book called “Practical Data Science with R.” The book has

Prefer = for assignment in R
www.r-bloggers.com

We share our opinion that = should be preferred to the more standard <- for assignment in R. This is from a draft of the appendix of our upc

Win-Vector Blog » How to outrun a crashing alien spaceship
www.win-vector.com

Hollywood movies are obsessed with outrunning explosions and outrunning crashing alien spaceships. For explosions the movies give the optima

Allen Bushnell, Fish Rap: Salmon on the prowl near the shore in Monterey...
www.santacruzsentinel.com

Allen Bushnell Fish Rap The weather forecasts a 4- to 6-foot northwest swell this weekend, but that shouldnt slow fishing down.