Andy Field just tweeted this: https://twitter.com/ProfAndyField/status/219757478018166784/photo/1 Filed under: news, serious stats Tagged: text books
Andy Field just tweeted this: https://twitter.com/ProfAndyField/status/219757478018166784/photo/1 Filed under: news, serious stats Tagged: text books
Last Friday, the National Research Council released a report titled Computing Research for Sustainability, written by the NRC’s Committee on Computing Research for Environmental and Societal Sustainability, on which I served (press release). Thi...
Meet the Skeptics: Why Some Doubt Biomedical Models - and What it Takes to Win Them Over: Kristin Sainani at Biomedical Computation Review has a nice article on skepticism of mathematical/computational modeling in biology. She also wrote the very nice
I was at a talk awhile ago where the speaker presented tables with 4, 5, 6, even 8 significant digits even though, as is usual, only the first or second digit of each number conveyed any useful information. A graph would be better, but even if you’re too lazy to make a plot, a bit [...]
I recently came across Luk Arbuckle, who wrote a series of posts about accepting the null hypothesis after a failure to reject, so I thought I'd pass them along. Luk makes a series of points in three separate posts, each of which I address formally in ...
When I need to graph a function of two variables, I often choose to use a contour plot. A surface plot is probably easier for many people to understand, but it has several disadvantages when compared to a contour plot. For example, the following statements in SAS/IML Studio displays a [...]
All sorts of numbers are used to describe us. The following numbers (with a few alterations to protect the innocent) can be used to describe me: 70, 50, 44, 145, 18, 2013, 176, 12438756, 51008420, 3, 0.25, 2, 26, 6439801802, … Continue reading →
There’s a lot of activities in the realm of Open Government Data OGD in the past few days. opendata.ch In Switzerland the second opendata.ch event was held in Zürich on 28 June (agenda and documents in German). Presentations from Rufus Pollock and Nigel Shadbolt (in English) will be available on opendata.ch. Zürich used opendata.ch 2012 …Read More
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Topological data analysis (TDA) is a relatively new area of research that spans many disciplines including topology (in particular, homology), statistics, machine learning and computation geometry. The basic idea of TDA is to describe the “shape of the data” by finding clusters, holes, tunnels, etc. Cluster analysis is special case of TDA. I’m not an [...]
A really nice explanation of the elements of Obamacare. Rafa’s post on the new inHealth initiative Scott is leading got a lot of comments on Reddit. Some of them are funny (Rafa’s spelling got rocked) and if you get past the usual level of...
Just in time for the hot weather . . . Aleks points me to this link to a graph of % check-ins at NYC ice cream shops plotted against temperature in 2011. Aleks writes, “interesting how the ice cream response lags temperature in spring/fall but during the summer, the response is immediate.” This graph is [...]
Using packages such as ggplot and lattice can produce some great charts and visualization, but googleVis is tough to beat for interactive charts to share on the web. Click on the image below to open up the html page. This was all done in R! I will warn you that it is too easy to … Continue reading →
Instructors seek examples of using the book, Doing Bayesian Data Analysis, as part of a course. A cursory web search yielded these few listed below, but there must be others. For example, my own course web page did not show up in the search, nor did an...
Data analysis recipes: Fitting a model to data: We go through the many considerations involved in fitting a model to data, using as an example the fit of a straight line to a set of points in a two-dimensional plane. Standard weighted least-squares fitting is only appropriate when there is a dimension along which the [...]
One popular trend in presenting results is the "coefficient plot," an alternative to the table of regression coefficients. I am seeing this a little more often in political science research and have received a few requests for code, so I thought I'd wr...
I’ve been playing with the igraph package a bit lately (see previous post HERE) and wanted to approach a problem I once visited in the past. The basic gist of the problem is this: Students in a class are asked … Continue reading →
I am in the slow process of developing a package to bridge structured text formats (i.e. classroom transcripts) with the tons of great R packages that visualize and analyze quantitative data (If you care to play with a rough build … Continue reading →
Jordan G. sent us to this Wikipedia image. (link) Intriguing concept to try to show the tit-for-tat in the space race between US and USSR. But it's almost impossible to fish any information out of it. While the voluminous text...
Euro 2012 is reaching its apex, and the final to be played on Sunday is between Spain and Italy. Yes, this is the Italian team that Spain let off the hook during the group stage. The Spanish team had 90 minutes to think about their strategy and a crucial two or three minutes at the end of their match against Croatia to give Italy the "biscotto". If Spain did that,…
I have sometimes heard complaints from collaborators that it will be impossible to have their work published in the mainstream literature unless a p-value is reported. This post is to report yet another counterexample that was recently published; a meta-analysis for the odds of perioperative bleeding complications in patients taking one of several anticoagulant/antiplatelet drugs. [...]
OK. Indeed, R has a longer learning curve than other systems, but don’t let that put you off! Once you master the syntax, you have control of an immensely powerful statistical tool. Actually, much of the syntax is not all that difficult. Don’t believe me? To prove it, let’s look at some syntax for providing summary statistics on a continuous variable.
So for example let's say you have 20 items each on a 1 to 7 scale. For most items, a 7 may indicate a positive attitude toward some issue, but for a few items, a 1 indicates a positive attitude. I want to show you a very quick and easy way to reverse code them using a single command line. This works in any software.
