# RDS Analyst Manual

(Difference between revisions)
 Revision as of 05:07, 5 April 2013 (view source) (→The Population menu)← Older edit Revision as of 05:07, 5 April 2013 (view source) (→The Population menu)Newer edit → Line 322: Line 322: * [http://ifellows.ucsd.edu/pmwiki/pmwiki.php?n=Main.Descriptives Descriptive Estimates]: This produces estimates of the population means, medians, quantiles, standard deviations  and extremes. * [http://ifellows.ucsd.edu/pmwiki/pmwiki.php?n=Main.Descriptives Descriptive Estimates]: This produces estimates of the population means, medians, quantiles, standard deviations  and extremes. * [http://ifellows.ucsd.edu/pmwiki/pmwiki.php?n=Main.ContingencyTables Population Crosstabs]: Cross tabulations of categorical variables. They include tests (which are dubious because of the dependence). * [http://ifellows.ucsd.edu/pmwiki/pmwiki.php?n=Main.ContingencyTables Population Crosstabs]: Cross tabulations of categorical variables. They include tests (which are dubious because of the dependence). - * [http://ifellows.ucsd.edu/pmwiki/pmwiki.php?n=Main.ContingencyTables Population Test Diffference in Proportions]: Test the hypothesis that two population proportions are equal. + * Population Test Diffference in Proportions: Test the hypothesis that two population proportions are equal. The basic descriptive, cross-tabs and frequencies use the current weights. These are stored in the data and added whenever estimates are computed. The default is the Gile sequential sampling (SS) weights. The basic descriptive, cross-tabs and frequencies use the current weights. These are stored in the data and added whenever estimates are computed. The default is the Gile sequential sampling (SS) weights.

## Contents

### Introduction

RDS Analyst (RDS-A) is a software package for the analysis of Respondent-driven sampling (RDS) data that implements recent advances in statistical methods.

RDS Analyst has an easy-to-use graphical user interface to the powerful and sophisticated capabilities of the computer package R. RDS Analyst provides a comprehensive framework for working with RDS data, including tools for sample and population estimations, testing, confidence intervals and sensitivity analysis.

Example capabilities are an easy format for entering data, the visualization of recruitment chains, regression modeling, and missing data.

The interface of RDS Analyst is similar to SPSS. RDS Analyst is also a free, easy to use, alternative to proprietary data analysis software such as SPSS, STATA, SAS/JMP, and Minitab. It has a menu system to do common data manipulation and analysis tasks, and an Excel-like spreadsheet in which to view and edit data.

RDS Analyst is meant for users who want to use state-of-the-art techniques for estimation and quantification of uncertainty from data collected via RDS. It represents advanced, comprehensive and open-source software to visualize, model and conduct sensitivity analyzes for RDS data.

RDS Analyst is an intuitive, cross-platform graphical data analysis system for the analysis of RDS data. It uses menus and dialogs to guide the user efficiently through the data manipulation and analysis process, and has an Excel-like spreadsheet for easy data frame visualization and editing. It is also the front-end to the very powerful capabilities accessible via the R command-line interface and also the extensive capabilities of the R statistical language.

## Current State

• It is an betaversion and is under continuous development and should not be distributed. Any requests for copies should be directed to the Hard-to-Reach Population Methods Research Group (HPMRG) [Lisa, Krista, Cori, Ian, and Mark]. This is because this version has advanced code in it and will have bad bugs. We want to support the program and do not want immature versions floating around that give it a bad name and which we will not be able to stamp out.
• The current version number is 0.1.

## Basic facts

• RDS Analyst is written for the R statistical environment.
• The current development form is for Windows and Macintosh. A LINUX version will be available in installers when it is released publicly.

The purpose of the initial beta test stage is to:

• Find basic installation and running problems in real-world environments.
• See if the GUI design will work for your RDS users. How can we improve on it?
• See if the current (basic) features work as you expect.
• Suggest features that we can add in future versions.

## Installation

### Installation on an Windows PC

The installer is at:

and for the latest and secure version of Java:

This can install all programs and utilities needed. If you already have some elements installed you can deselect (or cancel) during the installs. It is recommended that you install this all the first time. This installer is over 110Mb in size and will take time to download.

A reboot is not required. You do not need to uninstall any components to update (This includes R and Java). However the RDS Analyst application or the R application must not be running when you update.

You need the Java Runtime Environment to use RDS Analyst. If you get the message A JRE has been found. Do you want to install another one anyway?, it means that Java is already installed. In this case, click No and so as to not reinstall it.

Note for experienced users: This creates a private version of R for RDS Analyst to use and ensures RDS Analyst has the right version of R available for its use. If you already have R installed separately, the two versions will peacefully coexist and you can use the other version of R just as you were originally.

Finally, be sure to sign up for the RDS Analyst Users Group.

### Installation on an Apple Macintosh

There is a version for Apple Macintosh computers. They must have Intel CPUs (i.e., be purchased post-2006). To install:

A reboot is not required. You do not need to uninstall any components to update (This includes R and Java). However the RDS Analyst application or the R application must not be running when you update.

RDS Analyst uses Java to work. The last update for Mac OS X, Mountain Lion (aka 10.8) available since July 2012 does not come with Java pre-installed. You can check to see if you have java installed at http://javatester.org/version.html If you need to install Java, it is http://hpmrg.org/software/jre-7u11-macosx-x64.dmg

The RDS Analyst application and R will be in your Applications folder. To run RDS Analyst, double-click on it in the Applications folder.

After you install, you should use the updater to keep your installation to the latest version of the packages:

This just installs the core packages (that is, anything that has changed since the full install was made). It will typically be a few Mb in size.

Note: To use RDS Analyst, you need Java installed on your Mac. If you are using Mac OS X 10.6 and below, Apple's Java comes pre-installed. If you are using Mac OS X 10.7 (Lion) or Mac OS X 10.8 (Mountain Lion) and above then Java is not pre-installed. To install Java version 6, open the "Java Preferences.app" located in the Applications > Utilities folder on your Mac. It will ask if you want to install Java if it is not already there. Accept it's invitation.

Finally, be sure to sign up for the RDS Analyst Users Group.

## Starting RDS Analyst

To start RDS Analyst, select the RDS Analyst menu under Programs, and select the RDS Analyst program there. Alternatively, if you installed the desktop icon or the Quick Launch icon (the default), you can double-click on one of these to start the program. It will start the graphical-user interface. It may take a minute to do this but it is fast once loaded.

The package has two main windows. The primary one is titled the "Console" window. To do statistical analysis you choose the menus on top of the Console. The Console also records a log of all the commands and output produced from them. The other window is titled the Data Viewer. This is where the data are displayed and can be edited. The "Data Viewer" provides an easy to use, spreadsheet-like environment to view and edit data. Copy and pasting is supported, and is compatible with Excel 2003/2007, so data can be moved from Excel by simply copying it to the data viewer. Contextual menus can also be used to insert, delete and copy rows and columns.

Once the application starts up, you may need to load the Data Viewer window if it is not visible. In the "Console" window, go to "Packages & Data" menu item, select "Package Manager, and click the boxes next to "DeducerRDSAnalyst" under the "load" and "default" columns (two boxes will need to be clicked). This creates the "Data Viewer". Subsequent openings of the "RDS Analyst" had the "Data Viewer" window open from the beginning and this only needs to be done the first time.

The first thing to do is to let RDS Analyst know where the directory where the data is and where the files associated with the project will be stored. This is referred to as the can be typically is the "working" directory, and the program will read and save the files from there by default.

To do this, select the Set Working Directory menu item from the Console File menu. Then, typically, choose the directory where the data is stored.

## Quick start demo

There is a video tutorial to get you started. You can run it from the button on the "Data Viewer" window or directly at

Below is a step-by-step tutorial in words.

### Reading the NY Jazz dataset from RDSAT

• Use the dialog boxes to select the file nyjazz.rdsat from the directory "RDS Analyst Example Data Sets" which is on your "Desktop". (Hint: If it does not appear, look in "C:\Program Files\RDS Analyst\R-2.15.0\library\RDSdevelopment\extdata".
• The data is read in as a RDS format and with a (rds) preface to indicate it is an RDS data set (rather than just a regular spread sheet, say).

### Looking and editing the data in the spread sheet (the Data Viewer)

• Go to the Data Viewer window and note that the (rds) nyjazz data set is selected in the Data Set menu (center of the window pane). If you load more than one data set you can select the one to view here.
• Hee you can look at the data in "spread-sheet format". There is more information on the "Data Viewer" here
• On top of the spread-sheet are three tabs:
• "Data View" which is the current spread-shhet view
• "Variable View" which summarizes the variables and their properties.
• "RDS" where you can add information about the data set (such as estimates of the population size). It is OK to go with the default values for now.
• Click on the Variable View tab. Click the value for Gender.MF. under the Type column and select Factor value. Repeat for Race.WBO., Airplay.yn., and Union.yn.. This makes sure that the program recognizes them as categorical variables.
• Click on the RDS tab. Click the value for Mid box in the Population Size Estimate section. Enter an estimate of the population size for the NY jazz population. While this is unclear, a possible value is 20000. It is used in the computations, but they are somewhat insensitive to it (as long as it is not close to the sample size).

### Looking at the data (the Plots menu)

• Select Plot Recruitment Tree from the Plots menu. Select Run. The plot will appear in a new graphics window (called "JavaGD (2)", ha ha). This plots the recruitment trees, labeling each node by its ID. There are options in the dialog box you can play with to get different views. Select the "File" menu from the "JavaGD (2)" window to save the file as a PDF, JPG, etc.
• Select Recruitment Diagnostics from the Console Plots menu. Unselect the Recruitment tree box and select the Network size by wave box. Click Run. This is a plot of the network size distributions by the wave number of the respondent.

### Looking at the data (the Sample menu)

This is for exploratory data analysis.

• Select Contingency Tables from the Sample menu.
• Select Gender.MF. as the Row and Race.WBO. as the Column
• Click the Run button
• Look in the Console window for the results. On top of the console window there are two tabs Console view and Element View. The Console view gives a continuous view of the commands sent to the RDA Analyst engine. The Element View shows the results of each command separately, and is usually better. Click on the Element View tab.
• The results are in a contingency table output followed by a test of independence of the two factors.

### Analyzing the data (the Population menu)

• Select Frequency Estimates from the Population menu.
• Select Gender.MF. as the Variables using the arrow buttons.
• Click the Run button.
• Look in the Console window for the results. This uses a computationally-intensive algorithm to compute the confidence interval and will take 20 seconds or more to return output to the Console window. The output is a summary table with the pint estimate and the 95% confidence intervals. it also reports the design effect, standard error and the sample size (the last is adjusted for any missing values. For the nyjazz data set 21 of the 264 respondents did not report a network size).

### Saving the data

• To save the data and any edits to it in a file, choose Save Data from the File menu in Console. You can save it anywhere. It will save it with a .rdsobj so that next time you read it in the program will know that it is an RDS data set and not ask you to reenter all the information again.

### Saving the results

• To save the results in a file, choose Save from the File menu in Console, and make sure Results is selected from the Options:. You will need to add an extension to the file name, and we suggest txt (e.g., the file name rdsat_simple.txt). This should be open with, e.g., WordPad under Windows as it is a simple text file.
• To save the commands used to create the output in a file, choose Save from the File menu in Console, and make sure Commands is selected from the Options:.
• To save the complete output (results interspersed with the commands that produced them) in a file, choose Save from the File menu in Console, and make sure Complete output is selected from the Options:.

## Getting started (seriously)

Once the application starts up, focus on the (top) Data Viewer window. This is where you read in the data. The other window is Console is where most of the analysis takes place. It also records a log of all the commands and output. It can be ignored for now.

## The Windows

The "Console" window has three parts to it. The panel along the left side is a navigation panel. You can use it to quickly go from one statistical output to another. You can also remove output that you don't want by selecting it in the navigation panel and pressing theRemove button at the bottom of the navigation panel. The panel along the bottom is a command console. You can type in commands in the R language here. The panel in the upper right, which takes up most of the screen, is the output window. By default, RDS Analyst commands that are submitted for execution show up as red text and the generated output shows up as blue text. There are two tabs at the top of the output panel. Console view shows all the output, like one long ream of paper. Element view shows you just a single output element at a time, without any red RDS Analyst commands. You can click between these to get a view of the last entered and the history of the commands and output.

RDS Analyst can read in a wide range of data formats from other packages including SPSS (*.sav), SAS export (*.xpt), and Excel (via *.xls and other native Excel formats). It can also read in Comma separated (*.csv) files. For a general description of this, see Open RDS Data Set.

It also directly reads in RDSAT files (they should be text files to be recognized automatically or else the correct variable names will not show up).

If it is not an RDSAT file, RDS Analyst expects the data to be in a "spread-sheet" format containing the RDS survey data with recruitment information. This should represent valid RDS survey data. The sheet must have one row for each respondent (i.e. case), and columns for each survey response variable. In addition, the recruitment information can be specified in two ways:

• Coupon format: Basically like RDSAT (whereby the first column is comprised of serial numbers, the second column is the network size data, the third column is the participant id numbers and the third, fourth and fifth columns are generally the recruitment coupons) but without the two header lines.
• Recruiter ID format: Here it expects columns with the following names:
• id: A column of integers giving unique ids for each respondent (i.e., row of the spreadsheet).
• recruiter.id: A column of ids indicating the recruiter for that respondent (that is id). Recruiters can be identified by elements of id or as 0 for seeds.

When you read in a RDS data file you will be presented with a screen to Load RDS Data dialog. This enables you to specify the coupon variables, the subject ID, the network size variable in the data, etc. This is essential to identify the RDS data set. You can also (optionally) set the maximum number of coupons, the population size estimate and other data set characteristics before the RDS data set is ready for use. When you are done, click Run" to create the data set. It will appear in the Data Viewer.

The package creates a spread-sheet with other information in it, like the recruiter.id: a column of integers giving the id of the recruiter for the respondent in that row. A value of 0 means the person was a seed. It also creates a variable called seed which is the id of the seed recruiter for the respondent in that row (that is, the recruiter of the recruiter, etc, until you find the wave 0 seed recruiter). It also creates a variable called wave which is the wave for the respondent in that row (that is, the number of recruiters one must go back to to find the seed for that person. The wave of a seed is 0. These variables are stored wit hthe data set and can be analysed like other variables, including subset selection in estimation.

• If you read in a RDSAT file the RDS data set is created automatically as it already has the necessary information in it. If you use a CSV file (e.g., from Excel) you will need to specify the type of formatting in the file in the dialog that is presented.
• For files in Coupon format, you will need to select the coupon and network variables. If the coupon variables follow the id and network size variable in column order then you only need to specify the maximum number of coupons. The program computes the recruiter.id variable for this information.
• For files in Recruiter id format, you will need to select the id, recruiter.id and network size variables.
• If the spreadsheet is called foo (say), the RDS data set is called foo and will appear with the (rds) prefix to let you know it is an RDS data set.
• You can read in and analyse multiple data sets at the same time. After you have read in the data, use the menu item under the Data Set options in the dialoges to specify the RDS data set you will be working on.

## Saving RDS data

RDS Analyst can save the data sets created in a wide range of data formats. We recommend it be saved as in the internal data format for R for easy later reading (*.rda).

For a description of this see Save RDS Data Set.

## The Data Viewer window

The RDS Analyst Console window has menus (at the top) for the basic capabilities of the package and a data viewer (below the top) for looking at our data.

You can move between the two windows by clicking on them, or by using the Window menu in the Console" to (re)open the Data Viewer.

The Data Viewer provides an easy to use, spreadsheet-like environment to view and edit RDS data (or in fact, any spreadsheet data you load). Copy and pasting is supported, and is compatible with Excel 2003/2007, so data can be moved from Excel to R by simply copying it to the data viewer. Contextual menus are used to insert, delete and copy rows and columns.

If there are any data frames loaded in the R session, they can be viewed by selecting them from the Data Set list. Data can be loaded into the R session by clicking Open RDS Data Set button in the top left hand corner. The Currently viewed data set can be saved using the Save RDS Data Set button directly to the right of the Open RDS Data Set button. The currently viewed data set can be removed from the R session by clicking the button in the upper right.

The data viewer has two modes Data view and Variable view which can be freely switched between them using the tabs. The Variable view enables you to edit the variable types of the data read in. Categorical variables (including binary variables) should be set to type Factor by clicking on their entry and selecting it from the menu.

For details see data viewer.

Important: When a menu item is chosen it opens a dialog box where the variables are selected, options are set and the computation is done by clicking the Run button. This creates output in the Console window (you will need to click over to it to see it). These results and output can be saved at any point (typically at the end of the session) by using the Save command (see below).

## The menu structure of the Console window

Most of the work is done using these menu. The menus on the top of the Console window are:

• File:
• Edit:
• Workspace:
• Data:
• Sample:
• Population:
• Plots:
• Packages & Data:
• Window:
• Help:

• Preferences: To change font, set the default "working" directory where files are looked for and saved, etc. There is a separate panel for RDS Analyst specific features called Data Viewer. This enables you to change the defaults (like if you are using the basic or professional version).
• Quit the program.

• Open a data set and save the current data set in a file.
• The Open Data menu item is the primary way to read in an RDS data set from a text, CSV or other data file.
• Set the default place RDS Analyst looks for data and saves output using the Set Working Directory item.
• Create, open or save text files using ""New Document"", ""Open Document"" and ""Save"", respectively. This is a simple editor for text files such as files of R commands or notes on the analysis.

• Copy, Cut and Paste text
• Undo and Redo
• Search and Find
• Increase or decrease the font size

Objects that you create during an RDS Analyst session are held in computer memory. The collection of objects that you currently have is called the workspace. This workspace is not saved on disk unless you tell RDS Analyst to do so. This means that your objects are lost when you close the program and not save the objects, or worse when the program or your system crashes on you during a session.

When you exit RDS Analyst, you will be asked if you want to save your workspace. This will allow you to have the same data sets available the next time you start RDS Analyst. This will help to resume work on a project at the same point.

You can open (previously saved) and save workspaces from this menu. So if you have multiple projects you can save the entire workspace for each project in a separate file. Then open them from this menu.

The Clear all item empties the workspace (that is, removes all objects). So you can Clear all items and then open a complete workspace you have saved before.

Note that the Opened workspace is added to the current one. So if you only want the original files you should Clear all first.

This is to recode and modify the data in the data viewer. This means you do not have to go back to SPSS, SAS or Excel to recode, etc.

The term "factor" in the underlying R engine designates a categorical variable. In general factors are nominal but we use factors to represent both ordinal and nominal variables. By labeling a variable as a factor, RDS Analyst will treat it appropriately when analyzing it.

Click on the links below to get help on the following capabilities:

• Edit Factor: Add or subtract the values of a categorical variable.
• Recode Variables: You can recode variables into variables with new names. From the Recode Variables dialog, select the recode you want to re-target from the Variables to Recode list (e.g. sex -> sex). Then click on the Target button on the right. That will let you type in the name of the new variable (e.g., sexMF). The recode with show something like sex -> sexMF. The original "sex" variable will be unchanged and "sexMF" will appear in the Data Viewer window.
• Transform the variables: These can be very complex, if needed.
• Reset Row Names
• Sort
• Edit Meta Data: Specify here the characteristics of the RDS data like the maximum number of coupons, the network size variable, the missing data symbol, and population size estimates.
• Convert to RDS: This is a direct and manual way to (re) convert a data set into an RDS data set. It is rarely used (as the program does this automatically) but can be useful if the automatic method missed something.
• If you read in data from a CSV or other spreadsheet file (i.e., not an RDSAT data file) and edit it to make it an RDS data set then an RDS data set is formed from the current state of the spread sheet. If the spreadsheet is called foo (say), the RDS data set is also titled foo.

This is for exploratory analysis of the RDS data. It is used to describe the characteristics of the sample.

It deals with continuous data, categorical data and descriptive data.

• Frequencies: Tables of one or more variables, possibly stratified by others (like SPSS)
• Descriptives: This produces sample summaries such as means, medians, quantiles, standard deviations and extremes.
• Contingency Tables: Cross tabs. They include tests (which are dubious because of the dependence).
• Recruitment Homophily: Compute a homophily measure for recruitment process. Do respondents differential recruit people like themselves?

Frequencies, Descriptives, Contingency Tables do not use RDS weights to compute population estimates (but rather are samples averages of the RDS data). The other entries act as if the data are an independent sample and are deliberately not RDS aware.

This computes estimates of the population characteristics based on the RDS sample. Specifically, the procedures use RDS weights to compute population estimates (rather than samples averages of the RDS data).

It deals with continuous data, categorical data and descriptive data and complements the Sample menu that describes the sample.

• Frequency Estimates: Tables of one or more variables, possibly stratified by others (like SPSS).
• Descriptive Estimates: This produces estimates of the population means, medians, quantiles, standard deviations and extremes.
• Population Crosstabs: Cross tabulations of categorical variables. They include tests (which are dubious because of the dependence).
• Population Test Diffference in Proportions: Test the hypothesis that two population proportions are equal.

The basic descriptive, cross-tabs and frequencies use the current weights. These are stored in the data and added whenever estimates are computed. The default is the Gile sequential sampling (SS) weights.

The most important entry is the Frequency Estimates entry which computes confidence intervals for population proportions. The default method is Gile's SS estimator. The confidence interval is computed using Gile's bootstrap method. This is a computationally-intensive procedure and can take a minute or longer to complete.

• Estimate the Homophily in the Population:
• Estimate the Differential Activity in the Population:

This is to look at the RDS data with an eye to using it to estimate population characteristics. This looks at diagnostics of the sampling and possible seed dependency.

• Plot Recruitment Tree: Produces a publication quality graphics plot of the recruitment tree.
• Bar plot of the number of recruits by wave
• Scatter plot of the respondent degree verses wave
• Histogram of the number of recruits for each respondent
• Bar Chart of the number of recruits from each seed
• Make all Diagnostics: Does all of the above
• Boxplots by wave, seed, etc:

The dialogs retain their current settings and produce a publication quality PDF plots.

• This enables you to re-open the Data Viewer and Console windows.
• This enable you to install additional packages for the underlying R engine and look at the packages currently loaded.
• This also allows you to edit and view any "objects" in the workspace, such as RDS data sets (spreadsheets with the prefix (rds)), spreadsheets (data.frames), functions, etc.

• We use this to go between the Console and Data Viewer windows and also to choose a graphics window.
• Lists the currently open windows to choose from.
• You can go here to choose a window to bring to the front to work on.

• To get help, choose R help from the Help menu. The first time it is used it will start a browser for help (which will take a minute to load).
• You can also get help on the RDS Analyst package here.

## Saving the results, the output and/or the batch commands that produced them!

When a dialog box is Run it creates output in the Console window.

To save the results in a file (typically at the end of a session), choose Save Console from the File menu in Console, and make sure Results is selected from the Options:.

To save the commands used to create the output in a file (typically at the end of a session), choose Save Console from the File menu in Console, and make sure Commands is selected from the Options:.

To save the complete output (results interspersed with the commands that produced them) in a file (typically at the end of a session), choose Save Console from the File menu in Console, and make sure Complete output is selected from the Options:.

## Example data

We have three data sets already stored within R and the example data file from RDSAT (nyjazz.rdsat) as examples.

• To find out about the faux, fauxmadrona, and fauxsycamore data sets, just use help (see above) and search for them by name. There are manual pages on them :-)

The nyjazz.rdsat file is stored in your desktop under the directory RDS Analyst Example Data Sets . It can be opened from the Open RDS Data Set dialog box (for example). It is the same as the RDSAT file nyjazz.txt with the extension changed to .rdsat so the package will recognize it automatically.

## Getting Help from within the package

To get help, choose RDS Analyst Introduction Manual from the Help menu. The first time it is used it will start a browser with the RDS Analyst manual page on the hpmrg.org wiki (which will take a few seconds to load).

• You can enter any term in the "Search" box and search all the documentation for it. Try e.g., "plot".

To get help on the graphical user interface, choose Deducer Help from the Help menu. The first time it is used it will start a browser with the Deducer page on the deducer.org wiki (which will take a few seconds to load).

• You can enter any term in the "Search" box and search all the documentation for it. Try e.g., "plot".

To get help on R, choose R Help from the Help menu.

• Click on an item to get help about R and to get started with R. The "An Introduction to R" is a particularly useful reference for beginners.
• Click on the packages tab to get specific help on packages (like RDS).

To get help, choose RDS Analyst Reference Manual from the Help menu. The first time it is used it will start a browser for help (which will take a few seconds to load).

• You can enter any term in the "Search" box and search all the documentation for it. Try e.g., "RDS-II".
• Click on the "00Index" tab and it will list all the function in the "RDS" package. Click on an item to get help.
• Click on the packages tab to get specific help on packages (like RDS).
• Click on the DeducerRDSAnalyst package to get help with the commands underlying some of the menus (except the RDS menu).
• Click on the RDSdevelopment package to get help with the commands underlying the 'menus.
• This gives help on the data sets.
• Click on e.g., RDS.I.estimates to get help on the RDS-I estimate function.

To get help on R, choose R Help from the Help menu.

• Click on an item to get help about R and to get started with R. The "An Introduction to R" is a particularly useful reference for beginners.
• Click on the packages tab to get specific help on packages (like RDS).

## Tips and FAQ

• Many dialogs have a Subset option. Use this to analyse a subset of the data set with the cases of your choice included. In the Subset box enter an expression for those you want to retain (e.g., HIV < 2) and click Run. This will analyse the data set for only the retained cases. See Subset for details.
• By default, RDS Analyst stores all your files in your Desktop. To change this, just choose Set Working Directory from the File menu.
• If you want to bring the Data Viewer to be the front window, you can select it under the Window menu. This works for the Console or any other window.
• If you close the Data Viewer, you can reopen it under the Packages & Data menu.

## Tutorials

These are pages created by Ian Fellows that illustrate simple exploratory analyzes.

## Credits for RDS Analyst

RDS Analyst is based on the Deducer software (written by Ian Fellows). We also use the Java based R GUI JGR which is closely integrated with Deducer. These guys deserve most of the credit for what we see.

## Common installation problems and bugs

• If the program crashes, try to delete the preferences file in your home directory. It is called .JGRprefrc
• If the program crashes on first use on a Macintosh, it is possible that Java (e.g. Java Runtime ENvironment (JRE)) is not installed. If this is so, see the note above in the Installation section on Java. Or you can jsut (re) install it directly. To do this go to http://support.apple.com/kb/DL1515.