Mathematical and Applied Statistics Lesson of the Day – The Central Limit Theorem Applies to the Sample Mean

$Mathematical and Applied Statistics Lesson of the Day – The Central Limit Theorem Applies to the Sample Mean$

Having taught and tutored introductory statistics numerous times, I often hear students misinterpret the Central Limit Theorem by saying that, as the sample size gets bigger, the distribution of the data approaches a normal distribution.  This is not true.  If your data come from a non-normal distribution, their distribution stays the same regardless of the […]

MCMC for Econometrics Students – III

March 20, 2014
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As its title suggests, this post is the third in a sequence of posts designed to introduce econometrics students to the use of Markov Chain Monte Carlo (MCMC, or MC2) methods for Bayesian inference. The first two posts can be found here and here, and&n...

fine-sliced Poisson [a.k.a. sashimi]

March 19, 2014
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As my student Kévin Guimard had not mailed me his own Poisson slice sampler of a Poisson distribution, I could not tell why the code was not working! My earlier post prompted him to do so and a somewhat optimised version is given below: As you can easily check by running the code, it does […]

LEGO Calendar: a Tangible Wall-Mounted Planner that Can be Digitized

March 19, 2014
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The LEGO Calendar [vitaminsdesign.com], developed by design and invention studio Vitamins, is a wall-mounted time planner that simply can be photographed to create an online, digital counterpart. The calendar is big, visible, tactile and flexible, as...

The time traveler’s challenge.

March 19, 2014
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Editor's note: This has nothing to do with statistics.  I do a lot of statistics for a living and would claim to know a relatively large amount about it. I also know a little bit about a bunch of other scientific … Continue reading →

How Americans vote

March 19, 2014
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An interview with me from 2012: You’re a statistician and wrote a book, Red State, Blue State, Rich State, Poor State, looking at why Americans vote the way they do. In an election year I think it would be a good time to revisit that question, not just for people in the US, but anyone around […]The post How Americans vote appeared first on Statistical Modeling, Causal Inference, and Social Science.

The closer you look, the more confused

March 19, 2014
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A twitter follower submitted this chart showing the shift in ethnicity in Texas: If you blinked, you probably took away the wrong message. Our "prior" tells us that the proportion of Hispanics has been rising quite rapidly in Texas. So,...

What is numbersense?

March 19, 2014
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It's Spring Break at NYU, which for professors, is not a break. I have been marking midterms for my business analytics class. Since I like to set open-ended questions (are there anything else in statistics?), I get a variety of answers. One of the questions helps clarify what I mean by numbersense. The question asks students to comment on the distribution of a variable (median income) in a dataset of…

What is numbersense?

March 19, 2014
By

It's Spring Break at NYU, which for professors, is not a break. I have been marking midterms for my business analytics class. Since I like to set open-ended questions (are there anything else in statistics?), I get a variety of answers. One of the questions helps clarify what I mean by numbersense. The question asks students to comment on the distribution of a variable (median income) in a dataset of…

Define functions with optional parameters in SAS/IML

March 19, 2014
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Last month I blogged about defining SAS/IML functions that have default parameter values. This language feature, which was introduced in SAS/IML 12.1, enables you to skip arguments when you call a user-defined function. The same technique enables you to define optional parameters. Inside the function, you can determine whether the […]

MCMC for Econometrics Students – II

March 19, 2014
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This is the second in a set of posts about Monte Carlo Markov Chain (MCMC, or MC2) methods in Bayesian econometrics. The background was provided in this first post, where the Gibbs sampler was introduced.The main objective of the present post is to con...

HubCab: Mapping All Taxi Trips in New York during 2011

March 18, 2014
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The densely populated yet beautiful HubCab [hubcab.org] by MIT Senseable Lab is an interactive map that captures the more than 170 million unique taxi trips that were made by around 13,500 taxi cabs within the City of New York in 2011. The map shows...

Those wacky anti-Bayesians used to be intimidating, but now they’re just pathetic

March 18, 2014
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From 2006: Eric Archer forwarded this document by Nick Freemantle, “The Reverend Bayes—was he really a prophet?”, in the Journal of the Royal Society of Medicine: Does [Bayes's] contribution merit the enthusiasms of his followers? Or is his legacy overhyped? . . . First, Bayesians appear to have an absolute right to disapprove of any […]The post Those wacky anti-Bayesians used to be intimidating, but now they’re just pathetic appeared…

Learn to Manage Data at useR! 2014 or Online April 25

March 18, 2014
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Before you can analyze data, it must be in the right form. Join me on April 25th for a 4-hour webinar that shows how to perform the most commonly used data management tasks in R. We will work through hands-on examples of … Continue reading →

Learn EDA (exploratory data analysis) from the experts

March 18, 2014
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The Facebook data science team has put together a great course on EDA at Udacity. EDA stands for exploratory data analysis. It is the beginning of any data analysis when you have a pile of data (or datasets) and you...

Where’s Rick at SAS Global Forum 2014?

March 18, 2014
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Once again I'll be at SAS Global Forum this year. The 2014 location is Washington, D. C., so I am looking forward to greeting many friends in the government and consulting sectors. I always enjoy talking with SAS customers about statistics, simulations, matrix computations, and the SAS/IML product, so here's […]

Omitting Constant may Introduce Biased Coefficients

March 18, 2014
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It is well known that dropping the constant in regression analysis may introduce bias. However, bias is really not the deeper issue.  The deeper issue is that by omitting the constant, you are specifying a very specific form for the relationship b...

March 18, 2014
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Last year at the Google I/O conference Mitchell Foley presented new developments of the Google Chart Tools API and one of the new features he mentioned were timeline charts (about 6 min into the talk). Timeline charts are a great way of visualising di...

Cover of my forecasting textbook

March 18, 2014
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We now have a cover for the print version of my forecasting book with George Athanasopoulos. It should be on Amazon in a couple of weeks. The book is also freely available online. This is a variation of the most popular one in the poll conducted a mon...

Bayesian First Aid: Pearson Correlation Test

March 18, 2014
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Correlation does not imply causation, right but, as Edward Tufte writes, “it sure is a hint.” The Pearson product-moment correlation coefficient is perhaps one of the most common ways of looking for such hints and this post describes the Bayesian...

sliced Poisson

March 17, 2014
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One of my students complained that his slice sampler of a Poisson distribution was not working when following the instructions in Monte Carlo Statistical Methods (Exercise 8.5). This puzzled me during my early morning run and I checked on my way back, even before attacking the fresh baguette I had brought from the bakery… The […]

CODE_n: Architectural-Scale Data Visualizations Shown at CeBit 2014

March 17, 2014
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I guess that CODE_n [kramweisshaar.com], developed by design agency Kram/Weisshaar, is best appreciated when perceived in the flesh, that is at the Hannover Fairgrounds during CeBit 2014 in Hannover, Germany. CODE_n consists of more than 3.000 square...

CODE_n: Architectural-Scale Data Visualizations Shown at CeBit 2014

March 17, 2014
By

I guess that CODE_n [kramweisshaar.com], developed by design agency Kram/Weisshaar, is best appreciated when perceived in the flesh, that is at the Hannover Fairgrounds during CeBit 2014 in Hannover, Germany. CODE_n consists of more than 3.000 square...