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Xipe is a statistical comparison program written by Beltran Rodriguez-Muller at San Deigo State University . Xipe provides a non-parametric statistical analysis of the distribution of samples to determine which samples are statistically significantly different.

Xipe is designed to compare two different populations, and identify the differences between those samples. It is not designed, nor is it really appropriate, to use it with more than two samples. For that, you should use a multivariate statistical analysis like PCA, CDA, or something similar.

Xipe uses the follwoing procedure:

- Sample independently from your two populations. From each population remove a number of elements (typically 5,000) and count how often each of the things in your population is removed.
- Repeat that sampling (with replacement) 10,000 times. This provides the number of times each element is
*observed*in the population. - Mix your two populations together and create a mixed population.
- Repeat the removal of 5,000 elments (or your preferred sample size), and the 10,000 repititions on the mixed population.
- From the mixed population, generate the counts of frequency with which everything
*should*be seen. The*expected*frequency. - Use the distribution of elements in the expected frequency to determine the statistical differences in the observed frequencies, with a user defined cutoff.

Xipe was designed to identify the differences in functions between microbial metagenomes. However, xipe can be used to determine the statistically significant differences between any samples, provided you have a name and a frequency.

We have a version of xipe written in Python and that does not require matlab. This command is simpler than that above and should work with Python 2.6 or 2.7. Try this version.

You can download the xipe version used here for your analysis. Use the *runxipe* command to run xipe

Typically, we make a control file (called *control.txt*), that looks like this:

xipe/input.1 xipe/input.2 [0.98] [5000] xipe/output

The file input.1 and input.2 are the two input files, the [0.98] is the confidence level, and the [5000] is the sample size. Then you can use *runxipe < control.txt* to run the command

- Xipe does not assume that your data is normally distributed. Since xipe is a non-parametric statistical method, you can use data with any underlying distribution. However, as with all statistical tests, if your data is heavily skewed, your results will be too!
- Xipe is fast. Like the wind
- Xipe has a cool name. You can't say that about the g-test.

Retrieve the results from a previous submission

To use xipe, you need to have a list of the functions present in your sample, and the counts of those functions. You can paste data into this website (or upload files), and run xipe to identify the differences in samples. Please make sure that you use the appropriate format (they are slightly different).

*To paste samples:**For file uploads*

Please paste the funtions and counts joined with a colon (**:**) or a comma (**,**). For example:

function 1 : 2134 function 2 : 12 function 3 , 1444

It doesn't matter if there are spaces either side of the colon or comma.

Please use tab separated text for file uploads, with the functions separated from the counts by a tab

Sample 1 | Sample 2 |
---|---|

Choose files for your samples | |

Or paste your data below | |

Please choose the sample size:

Please choose the confidence level: