Create a barebones R package from scratch

Criar pacotes para o R é muito fácil

Criar pacotes para o R é muito fácil

While we’re on an R kick, Hilary Parker described how to create an R package from scratch, not just to share code with others but to save yourself some time on future projects. It’s not as hard as it seems.

This tutorial is not about making a beautiful, perfect R package. This tutorial is about creating a bare-minimum R package so that you don’t have to keep thinking to yourself, “I really should just make an R package with these functions so I don’t have to keep copy/pasting them like a goddamn luddite.” Seriously, it doesn’t have to be about sharing your code (although that is an added benefit!). It is about saving yourself time. (n.b. this is my attitude about all reproducibility.)

I need to do this. I’ve been meaning to wrap everything up for a while now, but it seemed like such a chore. Sometimes I’d even go back to my own tutorials for some copy and paste action. Now I know better. And that’s half the battle.

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Using R in Nonparametric Statistical Analysis

Blog com vários tutoriais para usar estatísticas não paramétricas simples em R

Blog com vários tutoriais para usar estatísticas não paramétricas simples em R

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Why use R? Five reasons

Bom blogue, as principais razões para usar R

Bom blogue, as principais razões para usar R

Why use R? Five reasons.

In this post I will go through 5 reasons: zero cost, crazy popularity, awesome power, dazzling flexibility, and mind-blowing support. I believe R is the best statistical programming language to learn. As a blogger who has contributed over 150 posts in Stata and over 100 in R I have extensive experience with both a proprietary statistical programming language as well as the open source alternative.  In my graduate career I have also had the opportunity to experiment with the proprietary software SPSS, SAS, Mathematica, as well as MPlus.

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SPSS Internet Resources

Links para variados sites sobre SPSS

Links para variados sites sobre SPSS

The SPSS Inc website

SPSS are now owned by IBM. The following links lead to the appropriate IBM pages now.

http://www-01.ibm.com/software/analytics/spss/ The home page of the SPSS Inc. website
http://www-01.ibm.com/software/uk/analytics/spss/ SPSS Inc. UK page

(If at some future time SPSS Inc change the structure of their website, you may find that only the first of the above links still works.)

The ASSESS-NEWS list

http://www.jiscmail.ac.uk/lists/assess-news.html Information about it, and an archive of past messages.

Other useful links

news:comp.soft-sys.stat.spss The SPSS newsgroup (this carries fairly heavy traffic).

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SPSS Macros on the Internet

Alguns sites com macros para SPSS

Alguns sites com macros para SPSS

What sources of SPSS macros are available on the Internet?

Here are a few that I know about; I hope other people will tell us about ones that should be listed but aren’t.

An obvious starting point is SPSS Inc’s own Macro Library at http://www.spss.com/tech/stat/macros/ (it doesn’t contain very many, though, and they are statistical rather than utilities). If you are planning to adapt or write macros, it’s also worth seeing what’s in SPSS Inc’s AnswerNet Solutions. Go to http://www.spss.com/tech/answer/, specify Product; SPSS Base and Free Text: macro, then click on the page’s Search button.Raynald Levesque’s site http://pages.infinit.net/rlevesqu/ includes many pages on macros (including examples and some tutorial materials). But you should also look at the examples in his pages on syntax, as some of these are based on macros.

Newsgroups are also a useful source of macros. Searches of their archives can be very rewarding if you can get your search terms right (see our Other Internet Resources page).

Confidence intervals for proportions, differences between proportions and related quantities. See Dr Robert G. Newcombe’s home page at http://www.uwcm.ac.uk/uwcm/ms/Robert.html. Note that these are SPSS programs rather than macros, despite being described as macros by the author.

Polytomous logistic regression (of particular interest to users of SPSS 8.0 and earlier). For macros by John Hendrickx and Prof. Dr. Steffen Kühnel see http://www.sls.wau.nl/bk/bedrijfskunde/jhendrickx/spss/mlogist/

Regression: evaluating collinearity in models with interactions or non-linear terms. For a macro by Ben Pelzer, Manfred te Grotenhuis, Jan Lammers, John Hendrickx, see http://www.sls.wau.nl/bk/bedrijfskunde/jhendrickx/spss/perturb/perturb.html

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Read Histograms and Use Them in R

Bom tutorial para construir histogramas no R

Bom tutorial para construir histogramas no R

Tutorials,

How to Read Histograms and Use Them in R

By Nathan Yau
The chart type often goes overlooked because people don’t understand them. Maybe this will help.

The histogram is one of my favorite chart types, and for analysis purposes, I probably use them the most. Devised by Karl Pearson (the father of mathematical statistics) in the late 1800s, it’s simple geometrically, robust, and allows you to see the distribution of a dataset.

If you don’t understand what’s driving the chart though, it can be confusing, which is probably why you don’t see it often in general publications.

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IFORS Education Resources Project

portal com materal sobre Investigação Operacional, otimização e SADs

portal com materal sobre Investigação Operacional, otimização e SADs

Welcome to the International Federation of Operational Research Societies (IFORS) Education Resources Project

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How many statisticians does it take to split a bill?

stas

Bom blogue, bem disposto aborda diferenças entre estatística e ML

Bom blogue, bem disposto aborda diferenças entre estatística e ML

Some thoughts on the Fall term, now that Spring is well under way [edit: added a few more points]:

  • RMarkdown and knitr are amazing. When I next teach a course using R, my students will be turning in homeworks using these tools: The output immediately shows whether the code runs and what its results are. This is much better than students copying and pasting possibly-broken code and unconnected output into a text file or (gasp) Word document.
  • I’m glad my cohort socializes outside the office, taking each other out for birthday lunches or going to see a Pirates game. Some of the older PhD students are so focused on their thesis work that they don’t take time for a social break, and I’d like to avoid getting stuck in that rut.
    However! Our lunches always lead us back to the age old question: How many statisticians does it take to split a bill? Answer: too long. I threw together a Shiny app, DinneR, to help us answer this question.

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Using Dates and Times in R

Excelente sobre a utilização de tempos e datas no R

Excelente sobre a utilização de tempos e datas no R

Using Dates and Times in R

by Bonnie Dixon, 10 February 2014


Today at the Davis R Users’ GroupBonnie Dixon gave a tutorial on the various ways to handle dates and times in R. Bonnie provided this great script which walks through essential classes, functions, and packages. Here it is piped throughknitr::spin. The original R script can be found as a gist here.

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Learn R interactively with the swirl package

Um pacote R para construir lições interativas

Um pacote R para construir lições interativas

swirl is a software package for the R statistical programming language. Its purpose is to teach users statistics and R simultaneously and interactively.

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