r4stats.com 2014 in review

The WordPress.com stats helper monkeys prepared a 2014 annual report for this blog.

Here’s an excerpt:

The Louvre Museum has 8.5 million visitors per year. This blog was viewed about 260,000 times in 2014. If it were an exhibit at the Louvre Museum, it would take about 11 days for that many people to see it.

Click here to see the complete report.

Posted in R, Uncategorized | 1 Comment

SAS is #1…In Plans to Discontinue Use

I’ve been tracking The Popularity of Data Analysis Software for many years now, and a clear trend is the decline of the market share of the bigger analytics firms, notably SAS and SPSS. Many people have interpreted my comments as implying the decline in the revenue of those companies. But the fields involved in analytics (statistics, data mining, analytics, data science, etc.) have been exploding in popularity, so having a smaller slice of a much bigger pie still leaves billions in revenue for the big players.

Each year, the Gartner Group, “the world’s leading information technology research and advisory company”, collects data in a survey of the customers of 42 business intelligence firms. They recently released the data on the customers’ plans to discontinue use of their current software in one to three years. The results are shown in the figure below. Over 16% of the SAS Institute customers surveyed reported considering discontinuing their use of the software, the highest of any of the vendors shown. It will be interesting to see if this will actually lead to an eventual decline in revenue. Although I have helped quite a few organizations migrate from SAS to R, I would be surprised to see SAS Institute’s revenue decline. They offer excellent software and service which I still use, though not anywhere near as much as R.

The full Gartner report is available here.

SAS Attrition Plot

Posted in Analytics, R, SAS, SPSS, Statistics, Uncategorized | 15 Comments

Learning R: Live Webinar, Interactive Self-Paced, or Site Visit?

My recent blog post, Why R is Hard to Learn, must have hit a nerve as it was read by over 6,000 people in its first two days online.  If you’re using R to augment your work in SAS, SPSS or Stata or you’re considering switching to R, my workshops can help minimize many of those headaches by pointing out the commands and options that frustrate users of those packages the most. Also find out which of the thousands of R packages will give you the output you’re most used to.

My next two live webinars done in partnership with Revolution Analytics are in January:
R for SAS, SPSS and Stata Users
Managing Data with R (updated to include dplyr, broom, tidyr, etc.)
Course outlines and registration for both is here.

My R for SAS, SPSS and Stata Users workshop is also now available as a self-paced interactive video workshop at DataCamp.com.

I do site visits in partnership with RStudio.com, whose software I recommend and use in every form of my training.  If your company does its training through Xerox Learning Services, I also partner with them. For further details or to arrange a site visit, you can reach me at muenchen.bob@gmail.com.

Posted in R, SAS, SPSS, Stata | Tagged , , , , , | 1 Comment

Updated: Why R is Hard to Learn

I’ve updated one of my most widely read blog posts, Why R is Hard to Learn. It focuses on the aspects of R which tend to trip up beginners. The new version is over twice as long as the original and it is located under the Articles menu, making it easier to find. Of course my new interactive workshop on DataCamp.com and my up-coming webinars with Revolution Analtyics cover these trouble spots thoroughly.


Posted in R, SAS, SPSS, Statistics | Leave a comment

Adding the SPSS MEAN.n Function to R

SPSS contains a very useful set of functions that R lacks. If you’re lucky enough to have access to SPSS, you can use SPSS and R very well together. If not, it’s easy to add these functions to R. The functions perform calculations across values within each observation. Rather than limit you to removing missing values or not, they let you specify how many valid values you want before setting the result to missing. For example in SPSS,
MEAN.5(Q1 TO Q10) asks for the mean only if at least five of the ten variables have valid values. Otherwise the result will be a missing value. This “.n” extension is also available for SPSS’ SUM, SD, VARIANCE, MIN and MAX functions.

Let’s now take a look at how to do this in R. First we’ll create some data with different numbers of missing values for each observations.

> q1 <- c(1, 1, 1)
> q2 <- c(2, 2, NA)
> q3 <- c(3, NA, NA)
> df <- data.frame(q1, q2, q3)
> df
q1 q2  q3
1 1 2   3
2 1 2  NA
3 1 NA NA

R already has a mean function, but it lacks a function to count the number of valid values. A common way to do this in R is to use the is.na() function to generate a vector of TRUE/FALSE values for missing or not, respectively, then sum them. As with many software packages, R views TRUE as having the value 1 and FALSE as having a value of 0, so this approach gets us the number of missing values. The “!” symbol means “not” in R so !is.na() will find the number non-missing values. Here’s a function that does this:

> nvalid <- function(x) sum(!is.na(x))
> nvalid(q2)
[1] 2

So it has found that there are two valid values for q2. This nvalid() function obviously works on vectors, but we need to apply it to the rows of our data frame. We can select the first three variables using df[1:3] and then pass the result into as.matrix() to make the rows easily accessible by R’s apply() function. The apply() function’s second argument is 1 indicating that we would like to compute the mean across rows (the value 2 would indicate columns). The final arguments are the functions to apply and any arguments they need.

> means  <- apply(as.matrix(df[1:3]), 1, mean, na.rm = TRUE)
> counts <- apply(as.matrix(df[1:3]), 1, nvalid)
> means
[1] 2.0 1.5 1.0
> counts
[1] 3 2 1

We have our means and the counts of valid values, so all that remains is to choose our desired value of counts and accept the mean if the data have that value or greater, but return a missing value (NA) if not. This can be done using the ifelse() function, whose first argument is the logical condition, followed by the value desired when TRUE, then the value when false.

> means <- ifelse(counts >= 2, means, NA)
> means
[1] 2.0 1.5 NA

We’ve seen all the parts work, so all that remains is to put them together into a single function that has two arguments, one for the data frame and one for the n required.

mean.n   <- function(df, n) {
  means <- apply(as.matrix(df), 1, mean, na.rm = TRUE)
  nvalid <- apply(as.matrix(df), 1, function(df) sum(!is.na(df)))
  ifelse(nvalid >= n, means, NA)

Let’s test our function requiring 1, 2 and 3 valid values.

> df$mean1 <- mean.n(df[1:3], 1)
> df$mean2 <- mean.n(df[1:3], 2)
> df$mean3 <- mean.n(df[1:3], 3)
> df
q1 q2  q3 mean1 mean2 mean3
1 1 2   3   2.0   2.0     2
2 1 2  NA   1.5   1.5    NA
3 1 NA NA   1.0   NA     NA

That looks good. You could apply this same idea to various other R functions such as sd() or var(). You could also apply it to sum() as SPSS does, but I rarely do that. If you were creating a scale score from a set of survey Likert items measuring agreement and a person replied “strongly agree” (a value of 5), to only half the items but skipped the others, would you want the resulting score to be a neutral value as the sum would imply, or “strongly agree” as the mean would indicate? The mean makes much more sense in most situations. Be careful though as there are standardized tests that require use of the sum.

If you’re an SPSS user looking to learn just enough R to use the two together, you might want to read this, or to learn more you could take one of my workshops. If you really want to dive into the details, you might consider reading my book, R for SAS and SPSS Users.

Posted in Analytics, Data Mangement, R, SPSS, Uncategorized | 11 Comments

R Workshops Updated to Include the Latest Packages

Two new R packages are quickly becoming standards in the R community:
Hadley Wickham’s dplyr and tidyr. The dplyr package almost completely replaces his popular plyr package for data manipulation. Most importantly for general R use, it makes it much easier to select variables.  For example,

R workshop series presented at a major pharmaceutical company.

R workshop series presented at a major pharmaceutical company. Photography by Stephen Bernard.

if your data included variables for race, gender, pretest, posttest, and four survey items q1 through q4, you could select various sets of variables using:

select(mydata, race, gender) # Just those two variables.
select(mydata, gender:posttest)   # From gender through posttest.
select(mydata, contains("test"))  # Gets pretest & posttest.
select(mydata, starts_with("q"))  # Gets all vars staring with "q".
select(mydata, ends_with("test")) # All vars ending with "test".
select(mydata, num_range("q", 1:4)) # q1 thru q4 regardless of location.
select(mydata, matches("^q"))  # Matches any regular expression.

As I show in my books, these were all possible in R before, but they required much more programming.

The tidyr package replaces Hadley’s popular reshape and reshape2 packages with a data reshaping approach that is simpler and more focused just on the reshaping process, especially converting from “wide” to “long” form and back.

I’ve integrated dplyr in to my workshop R for SAS, SPSS and Stata Users, and both tidyr and dplyr now play extensive roles in my Managing Data with R workshop. The next Virtual Instructor-led Classroom (webinar) version of those workshops I’m doing in partnership with Revolution Analytics during the week of October 6, 2014.  I’m also available to teach them at your organization’s site in partnership with RStudio.com (contact me at Muenchen.bob@gmail.com to schedule a visit). These workshops will also soon be available 24/7 at Datacamp.com. “You’ll be able to take Bob’s popular workshops using an interactive combination of video and live exercises in the comfort of your own browser” said Jonathan Cornelissen, CEO of Datacamp.com.

Posted in Analytics, Data Mangement, R, Uncategorized | 4 Comments

R Passes SPSS in Scholarly Use, Stata Growing Rapidly

by Robert A. Muenchen

Here is my latest update to The Popularity of Data Analysis Software. To save you the trouble of reading all 25 pages of that article, the new section is below. The two most interesting nuggets it contains are:

  • As I covered in my talk at the UseR 2014 meeting, it is very likely that during the summer of 2014, R became the most widely used analytics software for scholarly articles, ending a spectacular 16-year run by SPSS.
  • Stata has probably passed Statistica in scholarly use, and its rapid rate of growth parallels that of R.

If you’d like to be alerted to future updates on this topic, you can follow me on Twitter, @BobMuenchen.

Scholarly Articles

The more popular a software package is, the more likely it will appear in scholarly publications as a topic and as a method of analysis. The software that is used in scholarly articles is what the next generation of analysts will graduate knowing, so it’s a good leading indicator of where things are headed. Google Scholar offers a way to measure such activity. However, no search of this magnitude is perfect and will include some irrelevant articles and reject some relevant ones. The details of the search terms I used are complex enough to move to a companion article, How to Search For Analytics Articles. Since Google regularly improves its search algorithm, I recollect the data for all years following the protocol described at http://librestats.com/2012/04/12/statistical-software-popularity-on-google-scholar/.

Figure 2a shows the number of articles found for each software package for all the years that Google Scholar can search. SPSS is by far the most dominant package, likely due to its balance between power and ease-of-use. SAS has around half as many, followed by MATLAB and R. Note that the general purpose software MATLAB, Java and Python are included only when found in combination with analytics terms, so view those as much rougher counts than the rest. Neither C nor C++ are included here because it’s very difficult to focus the search compared to the search for jobs above, whose job descriptions commonly include a clear target of skills in “C/C++” and “C or C++”.

From RapidMiner on down, the counts appear to be zero. That’s not the case, but relative to the others, it might as well be.

Figure 2a. Number of scholarly articles found for each software.

Figure 2a. Number of scholarly articles found for each software.

Figure 2b shows the number of articles for the most popular six classic statistics packages from 1995 through 2013 (the last complete year of data this graph was made). As in Figure 2a, SPSS has a clear lead, but you can see that its dominance peaked in 2007 and its use is now in sharp decline. SAS never came close to SPSS’ level of dominance, and it peaked in 2008.


Figure 2b. Number of scholarly articles found for the top five classic statistics packages.

Since SAS and SPSS dominate the vertical space in Figure 2a by such a wide margin, I removed those two packages and added the next two most popular statistics packages, Systat and JMP in Figure 2c. Freeing up so much space in the plot now allows us to see that the use of R is experiencing very rapid growth and is pulling away from the pack, solidifying its position in third place. In fact, extending the downward trend of SPSS and the upward trend of R make it likely that sometime during the summer of 2014 R became the most dominant package for analytics used in scholarly publications. Due to the lag caused by the publication process, getting articles online, indexing them, etc. we won’t be able to verify that this has happened until well into 2015 (correction: this said 2014 when originally posted).

After R, Statistica is in fourth place and growing, but at a much lower rate. Note that in the plots from previous years, Statistica was displayed as a flat line at the very bottom of the graph. That turned out to be a search-related artifact. Many academics who use Statistica don’t mention the package by software name but rather say something like, “we used the statistics package by Statsoft.”

Extrapolating from the trend lines, it is likely that the use of Stata among academics passed that of Statistica fairly early in 2014. The remaining three packages, Minitab, Systat and JMP are all growing but at a much lower rate than either R or Stata.


Figure 2c. Number of scholarly articles that reference each software by year, after removing the top two, SPSS and SAS, and adding the next two most popular, Systat and JMP.


Posted in Analytics, R, SAS, SPSS, Stata, Statistics | 25 Comments

Knoxville R Users’ Group Meets September 3rd

The Knoxville R Users Group (KRUG) is hosting a brown bag viewing of RStudio’s webinar “Interactive Reporting” at 11am, Weds 3-Sept-2014 in 427 Hesler on the UTK campus “Hill” .  Per RStudio.net, data scientist Garrett Grolemund and software engineer Joe Cheng will speak on how to make your R Markdown documents interactive, and then unleash the full flexibility of analytic app development with shiny.  Come join us!

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jpmml and R (Free Webinar)

This free, global webinar will provide an introduction to jpmml, the world’s leading open-source PMML scoring engine currently being utilized by companies such as Airbnb to rapidly deploy predictive models into production.

Webinar Format:
– What is PMML?
– Building a predictive model in R and exporting it to PMML format
– Deploying a PMML model into a cloud-based Openscoring service
– Scoring Google Spreadsheet data
– Scoring PostgreSQL data
– Scoring Hadoop data
– Q&A

– Villu Ruusmann, Creator of jpmml and Founder of Openscoring.io

This event is brought to you by The Orange County R User Group.


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The RSelenium R Package (Free Webinar)

The Orange County R User Group (OC-RUG) will soon host a free webinar on the new “RSelenium” R Package which provides a set of R bindings for the Selenium 2.0 webdriver using the JsonWireProtocol. Using RSelenium, you can automate web browsers locally or remotely in order to test various web apps, such as Shiny applications – for example.

Webinar Format:
– Introduction to the RSelenium R package
– Live Demonstration
– Question and Answer period

Date:  May 21, 2014 at 10 am Pacific (California) time
John Harrison, RSelenium package author/maintainer

For more information on the RSelenium package, please visit this site:


Please note that in addition to attending from your laptop or desktop computer, you can also attend from a Wi-Fi connected iPhone, iPad, Android phone or Android tablet by installing the GoToMeeting App.

Registration is below:


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