Educational Statistics Using R And R Commander

Try Stata, SAS or SPSS (if you must). From GUI to writing code: The R commander displays the code that it generates. Reshaping data frames. off() command to tell R that you are finished plotting; otherwise your graph will not show up. Most of these functions are part of the R base package. A bootstrap interval might be helpful. It was written as part of an applied statistics course, given at the Wellcome Trust Sanger Institute, Hinxton, UK. ¨ Your hand-computed values and R Commander values for mean and SD should be the same. R Commander is a standard R package and can be installed using the R Package Installer that is part of the standard R GUI, or from the RStudio Packages pane. Health Science Statistics using R and R Commander has been written for students, researchers and professionals who need a practical guide to the subject. NEW YORK — Andrew Yang’s office phone rang at 6 p. How to Install R and the ‘R Commander’ The ‘R Commander’ is a basic-statistics graphical user interface (GUI) for R, a free interactive programming language and environment. The R language is widely used among statisticians and data miners for developing statistical software and data analysis. Statistics is the study of data. 01 instead of 0. Consequently some knowledge of linear models is required (statistics. Let us start with a simple example. R is a system for statistical computation and graphics. Add a note about this bill. , pair of values) for the same samples. created an index of four components — dentists per capita (an indication of. Manipulating Variables in R At some point after you have begun working with R, it is likely that you will want to manipulate your variables and do such things as combine vectors or group participants differently than your original grouping. the data and R to analyze it. Why outliers detection is important? Treating or altering the outlier/extreme values in genuine observations is not a standard operating procedure. Calculating variance in R is simplicity itself. Exploring Data and Descriptive Statistics (using R) Oscar Torres-Reyna Data Consultant # Description of the command. However, it is increasingly. 0) calculation software based on R which provides a quite usable R GUI with a command line interface (The R console) a code editor, and various other things (data frame editor, etc. Personally, I am happy to use all well designed GUIs but as well see the power of language based command line interfaces – you need to work with both to be most effective. If there are several data sets in memory, you can choose among them, but only one is active. The focus is on understanding how t-tests are constructed, the intuition and interpretation behind them, and how R can help you to do t-tests more easily. Run R and R Commander. Assumptions. Canada’s educational system, which is ranked highly internationally,. txt” and select Save Link As … to save the dataset to your computer Read the dataset into R using the read. R makes it easy to store (as data frames) and process such data to produce some basic statistics. table() or read. Use Software R to do Survival Analysis and Department of Statistics, University of Kentucky c GPL 2. What is the probability that x is greater than 100? Using R commander/software. In this document, commands typed in by the user are given in red and responses from R are given in blue; R uses this same color scheme. We denote group i values by yi: > y1 = c(18. You can de ne your own classes by creating a list of class boundaries and using the breaks = command. Using the R Commander: A Point-and-Click Interface for R. All analyses and results, including figures and tables, can be reproduced by the reader without having to retype a single line of R code. Thus, users can take this code and modify it. A VIF for a single explanatory variable is obtained using the r-squared value of the regression of that variable against all other explanatory variables: where the for variable is the reciprocal of the inverse of from the. Topics include data exploration, estimation, hypothesis testing, linear regression analysis, and clustering with two appendices on installing and using R and R-Commander. For more on statistical analysis using R visit http://w. NA is also used to indicate missing data when R prints data: > xvar [1] 2 NA 3 4 5 8. SPSS, Minitab) and would like to investigate the flexibility offered by a command line package such as R. There is a growing awareness of the need to effectively analyze astronomical amounts of data, much of which is stored in Oracle databases. To enable easy use of R(and Rcmdr), some additional procedures have been developed for Rcmdrby Murray Logan. Rstudio is the Best IDE available as it is user-friendly, open-source and is part of the Anaconda platform. " (John Maindonald, R-help, January 2006) 1. R commands generated by the R Commander GUI appear in the R Script tab in the upper pane of the main R Commander window. The content focuses on the use of R, an open-source and freely available statistical analysis program, which is increasing in popularity in the primary literature. 14 to the object x. It is one of the most popular languages used by statisticians, data analysts, researchers and marketers to retrieve, clean, analyze, visualize and present data. Using the R command, I found out that pnorm(1. At this point GUIs are the only solution to make R accessible for “generation point-and-click” and bridge the divide. Health Science Statistics using R and R Commander by Robin Beaumont Chapter 14 Boxplots Learning Outcomes * = more advanced outcomes Learning outcome Tick box Be able to explain and provide examples of variables with different levels of measurement (glossary entry levels of measurement) q. Open domain language S was originally written at Bell-Labs. How to Install R and the ‘R Commander’ The ‘R Commander’ is a basic-statistics graphical user interface (GUI) for R, a free interactive programming language and environment. When to use it. The with( ) function applys an expression to a dataset. OVERVIEW: This workshop will introduce participants to the R environment for statistical computing through the. Despite considerable efforts to enhance the use of clinica. For example, a random variable x has a normal distribution with a mean of 55 and a standard deviation of 10. R is an open source statistical package that is finding favour in a wide variety of statistics applications. * Ernst Linder, Ph. The “nlines = 1” command tells R to only read one line of data, which can be useful if you're using the script window in R studio. In this case, you have two values (i. Descriptive Statistics. sciviews-specific Rcmdr SciViews-specific Functions RcmdrPager Pager for Text Files Recode Rcmdr Recode Dialog Scatter3DDialog Rcmdr 3D Scatterplot Dialog. in statistics. R Commander (described in more detail later) is a suitable option since it is both free of cost and equipped with the GUI. inches is an object that contains some number — one or millions — of heights. R for beginners: Using R Commander in introductory statistics courses A tutorial by D. Lab #1: Introduction to R The focus of this lab is to introduce you to R and the R Commander (a graphical user interface to R). builtins() # List all built-in functions options() # Set options to control how R computes & displays results ?NA # Help page on handling of missing data values abs(x) # The absolute value of "x" append() # Add elements to a vector c(x) # A generic function which combines its arguments cat(x) # Prints the arguments cbind() # Combine vectors by row/column (cf. Videos #01-08 were produced by Joshua Havelka. Dotplots, traditionally drawn with graphpaper and pen, used to be a popular way to display distributions of small, heavily tied, sets of values. Once the device driver is running, R plotting commands can be used to produce a variety of graphical. Graphing the results. It is a number to tell how well the straight line. Initially R was the preserve of trained statisticians. Univariate statistics are quite simple in R. R is a programming language or a software environment as they call it for scientific computing and graphics. uk Jan 2014 Preface This material is intended as an introductory guide to data analysis with R Commander. "At Wharton, the keystone of our research has always been the creation of knowledge through the analysis of empirical data," said Michael R. If you are more accustomed to manipulating and analyzing your data by using a series of menus, the R interface seems sparse. R is an open source statistical package that is finding favour in a wide variety of statistics applications. There are small differences in the appearance and use of the R Commander under Mac OS X and on Linux and Unix systems. R Language Tutorials for Advanced Statistics. The values of the estimated coe cients and statistics measuring the goodness of t are revealed through. VIF calculations are straightforward and easily comprehensible; the higher the value, the higher the collinearity. This function performs “Dunn's” test of multiple comparisons following a Kruskal-Wallis test. The data is found in Mario F. If he answered, he knew, he. In this clear and practical text, Graeme Hutcheson, introduces the basics of data analysis using R, and its graphical user interface, R Commander (Rcmdr) to those who have never used the package before. Pennsylvania finally will be doing the same, beginning. Note that there is also a command called min, but it does not work the same way. Statistics is the study of data. , for x <- c(val = TRUE). The with( ) function applys an expression to a dataset. One method of obtaining descriptive statistics is to use the sapply( ) function with a specified summary statistic. In R terminology, the column “group” is called factor and the different categories (“ctr”, “trt1”, “trt2”) are named factor. In this document, commands typed in by the user are given in red and responses from R are given in blue; R uses this same color scheme. This is one page of a series of tutorials for using R in psychological research. When Should You Use R? Though R is a great software, but it isn’t the right tool for every problem. Initially R was the preserve of trained statisticians. An R Introduction to Statistics. ), all online from within the web browser. These Oscar winners are from twelve consecutive years. The values of the estimated coe cients and statistics measuring the goodness of t are revealed through. R is a free software environment for statistical computing and graphics. R Commander was developed by John Fox, from McMaster University, to make it easier for students to comprehend how software can be used to perform data analysis without the complications of learning commands. BOTH S-Plus and R are also programming languages and hence allow one to do innovative things with the data. Then press and again. Lab #1: Introduction to R The focus of this lab is to introduce you to R and the R Commander (a graphical user interface to R). xx() and as. Overview of R, R-studio, R Commander In this course, students will be familiarized with statistical tools called R, with R-Studio, and R Commander, to enhance the ease of use for beginners. Use a text file to write and edit your R commands. RStudio is an IDE for using R. The guide follows a step-by-step approach using a sample data set to practice statistical testing and provides an explanation of why each test is most appropriate to the example. R is a language and environment for statistical computing and graphics. These are GUI packages that extend R and let you do. Staying in R Markdown means everything matches up with the data by default. It is not intended to replace a basic or other statistics text but rather to complement it, although it does. R is an open source statistical package that is finding favour in a wide variety of statistics applications. Computer simulation is a very useful tool in statistics; its importance. Installing R Commander After opening R, type the code “install. Make sure to use a capital R for the command. Descriptive Statistics with R Commander The following videos show how to extract basic descriptive statistics and construct histograms and box plots from simple data sets. The first statistical package I learned how to use was Stata, simply because the classes I was taking were taught using Stata. 1 The R command line environmnent. This would be a good step towards building a solid foundation in using R. Starting Out R is an interactive environment for statistical computing and graphics. 23 We have been using this function quite a bit to make multi-panel graphs but you will always want to use this command for linear model diagnostics or your will have to use the arrows above the plots to go back and see previous plots. It's pretty easy to learn using online tutorials, in particular John Verzani's tutorial which is a course in introductory statistics using R. The first part covers z-tests, single sample t-tests, and dependent t-tests. 32 (released in Nov 2012). RStudio is an active member of the R community. The with( ) function applys an expression to a dataset. R is an intimidating but powerful program that assumes an intimate knowledge of data formats and terminology not familiar to many language testers. How to do multiple regression using R Commander and R Testing the accuracy of your regression model 23/09/2015 Discovering Statistics Using R | SAGE Publications Ltd. table() directly. It is not used across the whole organization but among users of R, this is our preferred IDE for accomplishing any of our R work. R Commander (described in more detail later) is a suitable option since it is both free of cost and equipped with the GUI. Calculating variance in R is simplicity itself. So the p values can be found using the following R command: >. The National Center for Education Statistics (NCES) is the primary federal entity for collecting and analyzing education data in the United States and other nations. 2 Comparing proportions between two groups 49. R for beginners: Using R Commander in introductory statistics courses A tutorial by D. R has a built-in editor that makes it easy to submit commands selected in a script file to the command line. [5 marks]. The staffing coordinator at his New York law firm was calling. "R Statistics" does not treat statistical concepts in depth. Every R-graph in R itself could be copied to clipboard (CTRL+C for bitmap, CTRL+W for metafile) and pasted. In R, the replicate function makes this very simple. We use RStudio for all instances we might use R for. The purpose of this book This book started as a set of notes, titled "simpleR," that were written to fill a gap in documentation for using R in an introductory statistics class. The quantitative side is addressed using descriptive and inferential statistical analyses, all of which are presented and visualized within the statistical environment R (R Core Team 2017). The F Distribution Description. Over the last 50 years, statistics and data science have become an integral part of the United Kingdom curriculum. A slightly different syntax can be employed to define a custom output as required. Here, we’ll let R create the histogram using the hist command. IPSUR Does: This plugin for the R Commander accompanies the text Introduction to Probability and Statistics Using R by G. The r value is what is known as a correlation coefficient. I find it easiest to use RStudio. Many of you have heard of R (the R statistics language and environment for scientific and statistical computing and graphics). Introduction The R Commander is a free and open source user interface for the R software, one that focuses on helping users learn R commands by point-and-clicking their way through analyses. 1: It includes 3. This works good only when the data set is not too large. Much of what below comes from An Introduction to Statistics for Canadian Social Scientists, 3rd ed. It is a number to tell how well the straight line. , for x <- c(val = TRUE). An R Tutorial 1. Try Stata, SAS or SPSS (if you must). Olivia Vinson and Morgan Flaherty, both seniors, placed first and second, respectiv. Method: We conducted an instrumentation validation study using Qualtrics® web-based platform. One-sample hypothesis test Statistics & Math Majors. VIF calculations are straightforward and easily comprehensible; the higher the value, the higher the collinearity. …Now, part of the problem is that everything opens in separate windows. Numerical methods, such as solving partial di erential equations; try Mat-lab. 54 to get centimeters. R shines truly when one actually have to use statistics to infer information, say creation of neural networks or forecasting or the likes. The R project was started by Robert Gentleman and Ross Ihaka (hence the name, R) of the Statistics Department of the University of Auckland in 1995. Health Science Statistics using R and R Commander has been written for students, researchers and professionals who need a practical guide to the subject. After learning how to start R, the rst thing we need to be able to do is learn how to enter data into Rand how to manipulate the data once there. R Commander Miscellaneous Functions DeltaMethod: Confidence Intervals by the Delta Method b0 income b1 education b2 Estimate SE 2. A novel feature of this book is an introduction to Bayesian analysis. It contains the weight of plants obtained under a control and two different treatment conditions. The Statistics section only shows some of the available tests in the R Commander and does not explain when to use the different methods or which assumptions need to be made for them to be correct. Jay Kerns, is FREE (in the GNU sense of the word) and comes with a plugin for Rcmdr. Here, we’ll use the built-in R data set named PlantGrowth. It is a GNU project which is similar to the S language and environment which was developed at Bell Laboratories (formerly AT. Close this window when you are done. R and RStudio. (To produce this graph you do not need to learn R, you can do it by cutting and pasting. Note that there are GUI interfaces available such as Rcmdr however, to take full advantage of R’s capabilities, you need to learn R’s syntax. You will now have to redo the regression command, but you should now see r and r 2 on your screen. For more on statistical analysis using R visit http://w. Using R for psychological research A simple guide to an elegant language. The use of these packages, however, requires a basic understanding of the R programming/command language and an understanding of the documentation accompanying each package. A short list of the most useful R commands. Our team includes graduates from Mathematics and Statistics programs, PhDs in fields from Education to Computational Genomics. The R project was started by Robert Gentleman and Ross Ihaka (hence the name, R) of the Statistics Department of the University of Auckland in 1995. The functions we are discussing in this chapter are mean, median and mode. The graphical user interfaces, such as R Commander, make R a bit more user friendly. R is built up using functions, some of which we can use on our symbolic variable (or object) a str() shows the structure of a in summary, it is numeric | here num, and has the value 2; length() tells us how long it is > str(a) num 2 > length(a) [1] 1 Roger Bivand Applied Spatial Data Analysis with R. The R Commander: A basic statistics graphical user interface to R. We believe free and open source data analysis software is a foundation for innovative and important work in science, education, and industry. In order to analyze data in R, you. Students from Wantagh High School have taken the top two spots in a local video competition about pedestrian safety. R has excellent packages for analyzing stock data, so I feel there should be a "translation" of the post for using R for stock data analysis. The Online Certificate in Applied Statistics using R has been developed for working professionals. Begin by installing R. Close this window when you are done. Lab 1: Introduction to R and RStudio The goal of this lab is to introduce you to R and RStudio, which you'll be using throughout the course both to learn the statistical concepts discussed in the textbook and also to analyze real data and come to informed conclusions. See also the important note on the course Requirements tab. Use Software R to do Survival Analysis and Department of Statistics, University of Kentucky c GPL 2. Health Science Statistics using R and R Commander has been written for students, researchers and professionals who need a practical guide to the subject. Here are two choices: from google and from Henrik Bengtsson. # Subset data in R Grade3Data<-subset(StudentData, Grade==3). R is a programming language or a software environment as they call it for scientific computing and graphics. Ana Nelson used her neat roux program to create a prettyprinted terminal session of running tutorial. R is an open source statistical package that is finding favour in a wide variety of statistics applications. What is R? How do I use it? R acts as an alternative to traditional statistical packages such as SPSS, SAS, and Stata such that it is an extensible, open-source language and computing environment for Windows, Macintosh, UNIX, and Linux platforms. Despite considerable efforts to enhance the use of clinica. Part 7 of this series showed how to do a nice bivariate plot, but it's also useful to have a correlation statistic. To use R, we need to install an Integrated Development Environment (IDE). An article a while back in The Washington Post confirmed what many of us who teach for a living increasingly suspected: that young people no longer read books. This tutorial will show you how to use SPSS version 12. Sometimes you will “lose” the screen you need to view. Creates a variable ('xvar') for a sample of 6 subjects, but the second subject is missing data for this variable. The highlight: figuring out the 15 or so commands to import, parse, slice and graph a 3-way comparison of control subjects using a scatterplot and a violin plot. • By using Rcmdr we will be mostly able to avoid the complexities of R, but still have access to free and powerful software. "paste" in Unix) diff(x) # Returns. 5 % b1 / b2 1. Your note is for you and will not be shared with anyone. R is a great way to do analysis,…but sometimes the interface could use a little help. R - Boxplots - Boxplots are a measure of how well distributed is the data in a data set. ” The design objectives of the R Commander were as follows: to support, through an easy-to-use, extensible, cross-platform GUI, the statistical functionality required for a basic-statistics course (though. Calculating variance in R is simplicity itself. — Margie, Hightstown, NJ, Introduction to R for SPSS Users student ***** “…It gives a good insight…” “I would recommend this workshop since it gives a good insight into the capabilities of R Commander and LessR. You can also add a title (main =), a label (xlab =), and color (col =). Any inappropriate statistics provided will result in a deduction of marks. builtins() # List all built-in functions options() # Set options to control how R computes & displays results ?NA # Help page on handling of missing data values abs(x) # The absolute value of "x" append() # Add elements to a vector c(x) # A generic function which combines its arguments cat(x) # Prints the arguments cbind() # Combine vectors by row/column (cf. Therefore, in order to be able to use the R Commander, you must install both R and the R Commander on your computer. I have recently re-installed R and R commander on my computer and there seems to no longer be the option of loading Excel files (when you go to Data --> Import Data --> *(there used to be an option of loading excel files at the end, but now i only have 4 options: "from text file, clipboard or URL", "from SPSS file. R-Commander is a graphical user interface for R, a statistical environment comparable to SPSS or SAS. How to control the limits of data values in R plots. One problem: That function does not exist in base R. R Commander allows the use of R without compromising the learning process as the command line interface to R can be an obstacle to many students (Fox, 2005). Used for studies with a binary response variable, that is the response can only have two values. However, except in rare situations, these com-mands will work in R on UNIX and Macintosh machines as well as in S-Plus on any platform. Even if the R commander does not do quite what is wanted, it may be possible to use R commander to generate relevant code, which can then be modi ed. Canada’s educational system, which is ranked highly internationally,. Health Science Statistics using R and R Commander has been written for students, researchers and professionals who need a practical guide to the subject. If you have a laptop with some other software you are of course free to bring that to the exercises. This makes analyzing and graphing your data in R a lot easier. The doBy package in R offers similar functionality and more. Here are some R Commander Tutorial Videos. We will not review them all here. If this happens, go to the taskbar at the bottom of your computer screen and click on the screen you need to see. with rows and columns. IPSUR Does: This plugin for the R Commander accompanies the text Introduction to Probability and Statistics Using R by G. If you are more accustomed to manipulating and analyzing your data by using a series of menus, the R interface seems sparse. It comes with Google Docs, Sheets, and Slides — and works seamlessly with Microsoft Office. Here we will talk about the base graphics and the ggplot2 package. But in some work environments it can take a lot of effort just to get the permission to install any executable on a machine. How to control the limits of data values in R plots. How to do multiple regression using R Commander and R Testing the accuracy of your regression model 23/09/2015 Discovering Statistics Using R | SAGE Publications Ltd. Create a vector of coefficients for a quadratic equation, using the sample function. In earlier R versions, isTRUE <- function(x) identical(x, TRUE), had the drawback to be false e. RcmdrPlugin. Your note is for you and will not be shared with anyone. developer-tools r-programming-language xfce. Rdata”) 16) What is the best way to use Hadoop and R together for analysis? HDFS can be used for storing the data for long-term. Use the Levene’s test of equality of variances through the leveneTest()command (See the One way ANOVA in R resource) If p<0. The R code below assigns some values to a variable (y), then plots a conventional dotplot, with duplicate values arranged evenly above and below. This can be done using the pmin command. 23 We have been using this function quite a bit to make multi-panel graphs but you will always want to use this command for linear model diagnostics or your will have to use the arrows above the plots to go back and see previous plots. Thus, in spite of being composed of simple methods, they are essential to the analysis process. Using data from a range of sources, including the Bureau of Labor Statistics and the U. You use the var() function. Second, install R-Studio from www. Education; Show more Show less. …Now, part of the problem is that everything opens in separate windows. Downloading/importing data in R ; Transforming Data / Running queries on data; Basic data analysis using statistical averages. R Commander is a GUI for the R programming language, licensed under the GNU General Public License, and developed and maintained by John Fox in the sociology department at McMaster University. …Another problem is that the default interfaces for R…look and act somewhat differently in each operating system. To create this R learning path, Analytics Vidhya and DataCamp sat together and selected a comprehensive set of resources to help you learn R from scratch. Explain how to communicate the outputs of data analysis using R language. Initially R was the preserve of trained statisticians. You can also add a title (main =), a label (xlab =), and color (col =). - Getting data into R. ” (Shiken: JALT Testing& Evaluation SIG Newsletter ) “Students, researchers, and others who wish to use R …. If you have an analysis to perform I hope that you will be able to find the commands you need here and copy/paste. Using data from a range of sources, including the Bureau of Labor Statistics and the U. Introduction The R Commander is a free and open source user interface for the R software, one that focuses on helping users learn R commands by point-and-clicking their way through analyses. It has R Commander which is a graphical user interface with menus to use in R. National Center for Education Statistics (NCES) The primary federal entity for collecting and analyzing data related to education in the U. R Beyond the R Commander R with RStudio The R Commander is more appropriate for the basic statistics course than for the intermediate course (though it would support both) Students in an intermediate course are better served by learning to write R commands Using R within the RStudio interactive development environment. Calculating variance in R is simplicity itself. Another way is to use the help command. Computer simulation is a very useful tool in statistics; its importance. It performed spectacularly. Hi, I usually use R to analyze statistics, specifically using R commander. Also, if you are an instructor and use this book in your course, please let me know. This function takes 3 arguments: the numeric variable, a categorical grouping variable and the function to apply. A brief introduction to linear models using the R Commander GUI to the R statistical software system. Here we will talk about the base graphics and the ggplot2 package. Pineo-Porter prestige score for occupation, from a social survey conducted in the mid-1960s. Linear regression is a type of supervised statistical learning approach that is useful for predicting a quantitative response Y. on a Friday. uk Jan 2014 Preface This material is intended as an introductory guide to data analysis with R Commander. R Markdown lets you weave in computations and graphs with the text you write: if you use other systems you will need to save out figures to import them, and copy-and-paste the values you compute. It performed spectacularly. Yeah haha I guess thats pretty trivial. This post has a good description of R Commander, and finds it easy to install, with many plug-ins available Trevor Kemmer, R within RapidMiner and RapidAnalytics We use R within RapidMiner and RapidAnalytics, because of the seamless integration and the ease of use of the overall data mining process. A short list of the most useful R commands. "Having used R Commander in my introductory statistics courses, I would recommend its use in a first course in statistics for several reasons. Newer users of statistical software or those unfamiliar with dictating code may prefer to use this methodology. 0 copyrighted Use offset() command to x one or more of the. Most of these functions are part of the R base package. One-sample hypothesis test Statistics & Math Majors. When R Commander starts up, there is no active data set. Once the device driver is running, R plotting commands can be used to produce a variety of graphical. Using R for statistical analyses - Multiple Regression. R Programming; Wikiversity. Health Science Statistics using R and R Commander has been written for students, researchers and professionals who need a practical guide to the subject. Close this window when you are done. The graphical user interfaces, such as R Commander, make R a bit more user friendly. R supports many functions for statistical analyses, but it does not incorporate statistical graphical user interface (GUI). Introduction to R. Objects can be assigned values using an equal sign (=) or the special <-operator. Rcmdr looks and works similarly to SPSS GUI by providing menu to analytics and graphical methods and display for each analysis run the underlying R code. The R Commander: A basic statistics graphical user interface to R. You use the var() function. (1 mark) Create a graph of the frequency distribution of highest education attained (educ_f) (1 mark). This author discusses basic statistical analysis through a series of biological examples using R and R-Commander as computational tools. from wikipedia IDE: An integrated development environment (IDE) is a software application that provides c. RData’ data set introduced in tutorial 3 and R Commander, create a table showing the frequency distribution of highest education attained (educ_f). What you have said is true about scenario analysis, but then R is meant for statisticians and written by statisticians. The R Commander is a free and open source user interface for the R software, one that focuses on helping users learn R commands by point-and-clicking their way through analyses. There is a book available in the "Use R!" series on using R for multivariate analyses, Bayesian Computation with R by Jim Albert.