GemStone is a professional application designed for the analysis of high-dimensional, flow cytometry data. Flow cytometry data analysis focuses on identification of populations in a sample and providing statistical results about those populations. Typically, regions are drawn on univariate or bivariate plots, and then used to create a hierarchy of subsets by "gating" the events. The resulting subsets are analyzed for frequency, intensity, and other common statistics to characterize the cells that were analyzed.

Cytometrists are trained to identify subsets of interest. We learn the characteristics of the subsets and which parameters are used to select them out of the many cell types that our samples contain. The learning curve can be long, and we often find it difficult to explain our plots and strategies with other scientists unfamiliar with cytometry.

1. Probability: the statistical likelihood of a particular event occurring. A PSM classifies events using probabilities rather than user-defined gates. The gating approach is subjective, and relatively small errors made in drawing gates are compounded with each subsequent gate in the hierarchy. By using probability, a PSM actually reduces the error with each additional parameter that is added to the model. The likelihood that you are actually identifying the cells you are interested in increases as you build a PSM.

2. State: a set of conditions that discretely characterize something. A PSM probabilistically classifies events into a set of states, based on the characteristics defined for each parameter. The state for each event can be thought of as an additional parameter, one that identifies the particular set of characteristics that define that state. GemStone uses the state as the common, X-axis for its parameter plots. This allows all parameters to be compared on a common axis, making it possible to correlate and compare all of the parameters in a single plot.

3. Model: a mathematical representation of a process. A PSM uses fitting routines to classify cells into the most probable states, or to adjust the model to match the data. Using this approach, GemStone can provide objective measurements of how well the model represents the data. There are no hard-edges in a PSM. The modeling process allows populations to overlap based on probabilities.

The license of this software is Free Trial Software, the price is $1500.00, you can free download and get a free trial.