RDS Analyst software was designed to help researchers visualize and analyze data collected via respondent-driven sampling designs.
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.
Java Runtime Environment is required for RDS Analyst, and is included as an optional component in the installer (requiring Administrative privileges on the machine). 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, you may click No so as to not reinstall it. You can check to see if you have java installed at http://javatester.org/version.html
Respondent-driven sampling (RDS) is a novel sampling technique that was designed to survey hard-to-reach populations such as sex workers or injection drug users.
The basic idea of RDS is that rather than randomly sampling some fraction of a target population -- and in situations where RDS is used there is probably no database of the population -- the sample begins with a few individuals ("seeds") who recruit more respondents. Those recruited then recruit additional respondents, as the sample traverses a social network. Through waves of sampling, a recruitment tree extends through the target population. The example recruitment tree below depicts a sample with 10 seeds that reached 264 people over 11 waves of sampling. (A thorough description of RDS is available here.)
RDS Analyst is essentially a set of tools to interpret data that has been collected in this way. It has functions to view, summarize and analyze data (see the help pages listed below). One of the main uses of RDS sampling and of this software is to estimate the prevalence of some characteristic in the population, such as an infection rate. This can be done using the Population > Frequency Estimates dialog.
RDS Analyst also has diagnostic tools to help interpret frequency estimates and other inferences made from the sample. In particular, see the Population Homophily, Differential Activity and Recruitment Diagnostics functions.