http://seticlassic.ssl.berkeley.edu/screensaver/data_analysis.html
Also this as well, for that of the following.
Best Gaussian
If a signal is above the average noise and also gets stronger and then weaker in a "gaussian"
fashion as the object passes through the telescope beam, we're interested!
The number labeled "power" tells us how strong the signal is relative to the baseline power
calculated above. The number labeled "fit" is a measure of how well the rising and falling signal
fits an ideal gaussian (bell curve) profile. A lower "fit" number means a better fit.
(It's actually a chi-square fit, ie. how far the data departs from an ideal gaussian.)
Even if you see a strong peak and a low fit number, do not call the press or announce to the
world that you have discovered the aliens. Any strong signal must be verified (several ways)
to rule out sources of radio-frequency-interference (RFI) before it becomes "official".
Since noise can sometimes randomly simulate a gaussian, we've set a threshold to avoid being
overwhelmed with trivial results. If the signals are stronger than 3.2 times the average noise
level that have a fit better (less than) 10, they are returned by the screensaver client to our
server in Berkeley. The graph below the power and fit numbers displays the curve fitting analysis
as it is happening and also displays the best gaussian so far for this work unit. Note: If the
telescope is slewing across the sky too slowly or too quickly during the observation, no graph
is drawn. The red line shows the actual data - power at a given frequency, as seen over time.
This view is a back to front slice of the big chart at the bottom of your screensaver display.
This aspect of the graph changes each time the gaussian fitting moves to a new frequency.
The white line shows best fit gaussian for that data, i.e. what your client is actually
calculating! At each data point we try a new fit. You see this as the white line changing very
quickly. If the analysis were not happening so quickly you would see the gaussian (the bump in
the white line) move from left to right across the graph as we try to best fit your data.
