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Log Window

This window is used to display the results of line position, line intensity, energy level or contour fits and will also display details of calculations if the PrintLevel is positive. For line position and intensity fits, a line list giving details of each fitted rotational line, with an observed and calculated frequency or intensity and obs-calc for each line, is also given. For a graph of the residuals, see the Residuals Window. Note that the information displayed applies to one fit cycle; as a non-linear fitting process is used expect to fit several times until convergence is obtained. Click on an item in the picture below for more information:


Fit Details
Observations
 nobs  = The number of lines fitted or the number of experimental points for a contour fit
Parameters
 npar = The number of parameters floated
Initial Average Error
 This is Σ[(obsi-calci)/wi]2/(nobs-npar) with the calculated values, calci, obtained using the parameters at their initial values.
Predicted New Error This is Σ[(obsi-calci)/wi]2/(nobs-npar) with the calculated values, calci, obtained from the non-linear least squares fit. They are typically close to the values that would be obtained from the new parameters, but are only exact if the calculated values are linear (or nearly linear) in the parameters. This is should be the case near to convergence, but often not when starting the fitting process. Fit again to find the true new error.
Old
 The parameter value at the start of the fit.
New
 The parameter value after the fit cycle.
Std Dev
 The estimated standard deviation of the parameter, based on the quality of the fit.
Sens
 Watson's sensitivity parameter (J. K. G. Watson, J. Mol. Spectrosc. 66, 500 (1977)) for the parameter. This is the change in the parameter that would make the average error of the fit increase by a factor of 0.1/npar, and provides a useful guide as to how many figures should be quoted for the parameter to ensure that the calculation can be reproduced. Where parameter correlation is high, this can be many more figures than suggested by the standard deviation of the parameter.
Summary
 The new parameter, with the one standard deviation in units of the last figure in brackets. The sensitivity is used to determine how many figures are displayed for the standard deviation.
Correlation Matrix The correlation between the parameters.

Buttons

Do fit of indicated type. For fits other than a Contour fit, the experimental information is taken from the file set at the top of the window. Alternatively, you can take the information from the clipboard by right clicking on the fit button. (This works well if you prefer to use Excel or another spreadsheet program to manage the experimental line list; before each fit select the required area of the spreadsheet and copy it to the clipboard.)
Line
 line position fit
Contour contour fit to current overlays
Intensity line intensity fit to line list in file shown
ELower
 Fit to the lower state energy
EUpper
 Fit to the lower state energy
Calibration
 Calibration Fit
Step constants back one fit cycle for each press
Step constants forward one fit cycle
Click to browse for experimental file name
Edit given file; this button will normally start the Slave Editor
Clear log window
Copy log to clipboard.
Save log to file.