Windows <Prev Next>

Residuals Window

This window is used to plot the observed - calculated values from a fit (or related quantities). Bring this up with View, Residuals if required.

The status bar displays the x, y co-ordinates of the mouse and, if the mouse is over an experimental point, the source of the data point. Note that you can often go directly to the source of the data by right clicking on a given point and selecting "Edit Point". This requires the Slave Editor to be set up.Note that the average error displayed at the top is slightly different to the value given in fits - it is simply [Σ[(obsi-calci)/wi]2/nobs]½, and does not take account of the number of parameters floated. (This allows a value to be calculated without doing a fit.)
Reload observations and recalculate residuals (equivalent to doing a fit with no parameters floated).
Select the Y axis of the plot. Possible choices are:
  • Weighted Obs-Calc
  • Unweighted Obs-Calc
  • Weighted (Obs-Calc)/Obs = Relative weighted error
  • Unweighted (Obs-Calc)/Obs = Relative unweighted error
  • Observed
  • Calculated
  • Observed and Calculated
  • Weight
The last 4 are not residuals, but can be useful for indicating the data included in the fit
Select the X axis of the plot. Possible choices are:
  • Observation Number
  • Frequency
  • State Energy (Use the "Upper" check box to select the lower or upper state)
  • Calculated value
  • Observed Value
  • Weight
  • Population
  • J
  • N
  • F
  • A: Ω for linear molecules, |K| for symmetric tops, Ka for asymmetric tops
  • B: F1, F2...for linear molecules, Kl for symmetric tops, Kc for asymmetric tops
  • F1 Hyperfine quantum numbers (if appropriate)
  • F2
  • ...
  • F9
Check to use upper (rather than lower) state quantum numbers or state energy.
Plot data with zero weight (which would otherwise not be plotted).
Zoom into region selected with mouse.
Zoom plot out.
Reset plot to fill window.