The National Ocean and Atmospheric Administration generates freely-available world-wide estimates of mean daily sea surface temperature, and has been doing so back to 1981. The data are on a 0.25 x 0.25 degree grid, and provide an interpolated estimate of the sea surface temperature for each day of the year, based on a ... [Read more...]

We had a marvellous series of guest posts here on the blog over the past few weeks. I'd like to give a special thanks to all of our guest bloggers for contributing, with special thanks to Joe Rickert for stepping in as our acting editor for the past 3 weeks. If ... [Read more...]

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Today I want to advocate weighted nonlinear regression. Why so? Minimum-variance estimation of the adjustable parameters in linear and non-linear least squares requires that the data be weighted inversely as their variances . Only then is the BLUE (Best Linear Unbiased Estimator) for linear regression and nonlinear regression with small errors (... [Read more...]

I used R package ChIPpeakAnno for annotating peaks, and found that it handle the DNA strand in the wrong way. Maybe the developers were from the computer science but not biology background. ?View Code RSPLUS1 Read More: 2754 Words Totally [Read more...]

Many articles have been written on why R is better than Excel for data analysis.  In this post, I will summarize the reasons why R is advantageous in most data[...] The post Why R is Better Than Excel for Fantasy Football (and most other) Data Analysis appeared first on Fantasy ... [Read more...]

I have created a new visualization in D3. The purpose is to aid in the interpretation of Cohen’s d. The visualization presents Cohen’s d in the following ways: Visually, Cohen’s U3, Probability of superiority, Percentage of overlap and Number needed to treat. The visualization should work on ... [Read more...]

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In this post, we'll explore a special type of nonlinear constrained optimization problems called quadratic programs. Quadratic programs appear in many practical applications, including portfolio optimization and in solving support vector machine (SVM) classification problems. There are several packages available to solve quadratic programs in R. Here, we'll work with ... [Read more...]

Now that the conference and the Bayesian non-parametric satellite workshop (thanks to Judith!) are over, with (almost) everyone back home, and that the post-partum conference blues settles in (!), I can reflect on how things ran for those meetings and what I could have done to improve them… (Not yet considering ... [Read more...]

Having just returned from the SICB 2014 meetings, the appearance of many people’s Powerpoint figures is fresh on my mind. The sheer number of tiny figure labels (tick marks, axis titles, legend text etc) is disappointing. If we want to point fingers, MATLAB users are clearly the worst offenders because ... [Read more...]

Visualization is a useful tool for data exploration and statistical analysis, and it’s an important method for communicating your discoveries to others. While those two uses of visualization are related, they aren’t identical. One of the reasons that I like ggplot so much is that it excels at ... [Read more...]

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This morning my wife presented me with a rather interesting statistic: a healthy couple has a 25% chance of conception every month [1], and that this should result in a 75% to 85% chance of conception after a year. This sounded rather interesting and it occurred to me that it really can’t be ... [Read more...]

I am teaching my Fisheries Science and Management course at Northland College this semester.  The science portion of the course is a fairly traditional treatment of population dynamic parameter estimation methods (using R with the FSA package, of course).  This semester … Continue reading → [Read more...]

IntroductionHoly crap, it was cold out.If you haven't been reading the news, don't live in the American Midwest or Canada, or do and didn't go outside the last couple weeks (for which I don't blame you) there was some mighty cold weather lately due to ... [Read more...]

Computer Science is no more about computers than astronomy is about telescopes (E. W. Dijkstra) Some days ago I published a post about how to build fractals with R using Multiple Reduction Copt Machine (MRCM) algorithm. Is that case I used a feature of the grid package that allows you ... [Read more...]

For my first experience with STAN I wanted to convert my last JAGS program into STAN. This was a bit more difficult than I expected. The JAGS program was Fe concentration in rainwater including values below detection level.DataData has been explained b... [Read more...]

Introduction There are no agreed-upon methods for inferring halocline depth, but a reasonable method might involve locating the depth at which dS/dp is largest, where S is salinity and p is pressure (Kelley 2014 chapter 5). Calculating the derivative using e.g. diff(S)/diff(p) can be problematic because of ... [Read more...]