2026 search results for "Ggplot"

How to tell when error bars correspond to a significant p-value

July 24, 2012
By
How to tell when error bars correspond to a significant p-value

Can you tell when error bars based on 95 % CIs or standard errors correspond to a significant p-value? Don’t fret if you think it’s hard, a study from 2005 showed that researchers in psychogoly, behavior neuroscience and medicine had a hard time judging when error bars from two independent groups signified a significant difference.

Read more »

Estimating required hospital bed capacity

July 23, 2012
By
Estimating required hospital bed capacity

Estimating required hospital bed capacity requires a thorough analysis. There are a lot of ways of approaching a capacity requirement problem, but I think we can agree that a simple spreadsheet analysis just won't cut it. The approach described in this post makes use of discrete-event simulation and, just to  Read...

Read more »

Estimating required hospital bed capacity

July 23, 2012
By
Estimating required hospital bed capacity

Estimating required hospital bed capacity requires a thorough analysis. There are a lot of ways of approaching a capacity requirement problem, but I think we can agree that a simple spreadsheet analysis just won't cut it. The approach described in this post makes use of discrete-event simulation and, just to clarify, makes abstraction from a lot of variables which should be taken into consideration in...

Read more »

Modeling Trick: Impact Coding of Categorical Variables with Many Levels

July 23, 2012
By
Modeling Trick: Impact Coding of Categorical Variables with Many Levels

One of the shortcomings of regression (both linear and logistic) is that it doesn’t handle categorical variables with a very large number of possible values (for example, postal codes). You can get around this, of course, by going to another modeling technique, such as Naive Bayes; however, you lose some of the advantages of regression Related posts:

Read more »

Map biodiversity records with rgbif and ggmap packages in R

July 23, 2012
By
Map biodiversity records with rgbif and ggmap packages in R

When I attended usrR! 2012 last month, there was an interesting presentation by Dr. David Kahle about the package ggmap. It is a package built over ggmap2 and helps us map spatial data over online maps like Google maps or Open Street Maps. I decided to give ggmap package a try with biodiversity data. So

Read more »

Map biodiversity records with rgbif and ggmap packages in R

July 23, 2012
By
Map biodiversity records with rgbif and ggmap packages in R

When I attended usrR! 2012 last month, there was an interesting presentation by Dr. David Kahle about the package ggmap. It is a package built over ggmap2 and helps us map spatial data over online maps like Google maps or Open Street Maps. I decided to give ggmap package a try with biodiversity data. So

Read more »

Time-based internet advertising

July 20, 2012
By
Time-based internet advertising

Last week it was announced that Facebook is rotating its ads after a certain time of exposure. Sid Suri, Preston McAfee, and Dan Goldstein's research may have been the source of this idea. In 2011 and 2012 the trio published a couple papers putting for and improving the idea. The post Time-based internet advertising appeared first on Decision Science...

Read more »

Health Care Costs – Part 3, "Why You Are Paying More"

July 19, 2012
By
Health Care Costs – Part 3, "Why You Are Paying More"

Malpractice - A Booming Industry? Perhaps authors Frank Sloan, Randall Bovbjerg and Penny Githens capture it best from their book Insuring Medical Malpractice: "If aging Doctor Kildare were to return to medical practice today, having been...

Read more »

Time zones

July 18, 2012
By
Time zones

Say we have some following raw data. It consists of a timestamp and a corresponding value. There is a peak at exactly midnight (00:00:00). Each timestamp is fully specified. It contains a date, a time of day, and a time zone offset indication. In this case +0000, meaning the data is 0 hours away the UTC timezone. "timestamp","value""25-04-2012...

Read more »

The R packages in a data scientist’s toolbox

July 17, 2012
By

John Myles White, self-described "statistics hacker" and co-author of "Machine Learning for Hackers" was interviewed recently by The Setup. In the interview, he describes his some of his go-to R packages for data science: Most of my work involves programming, so programming languages and their libraries are the bulk of the software I use. I primarily program in R,...

Read more »