VOStat - US Virtual Astronomical ObservatoryVOStat is a simple statistical web service that lets you analyze your data without the hassle of downloading or installing any software. VOStat provides interactive statistical analysis of astronomical tabular datasets. It is integrated into the suite of analysis and visualization tools associated with the Virtual Observatory (VO) through the SAMP communication system. A user supplies VOStat with a dataset and chooses among ~60 statistical functions, including data transformations, plots and summaries, density estimation, one- and two-sample hypothesis tests, global and local regressions, multivariate analysis and clustering, spatial analysis, directional statistics, survival analysis , and time series analysis. VOStat was developed by the Center for Astrostatistics (Pennsylvania State University).