User guide

Quantity One User Guide
15-10
Standards Regression Models
Select different regression models in the options dialog box while you study
the standard curve with the standard points displayed (see display options
below). Then choose a curve that best fits the data points. (The correlation
coefficient—see below—provides another measure of curve fit.)
Note: Note that point-to-point semi-log is the only method available if you
perform band matching on your image, because band matching adjusts
the positional values of bands in localized areas based on your
identification. Point-to-point semi-log is appropriate for this kind of
localized variation, whereas the other methods are not. Therefore, you
should select point-to-point semi-log if you intend to perform band
matching (required for similarity analysis) on your gel.
Point-to-point semi-log. This and the Elder-Southern method are especially
useful for describing band migration in static-field electrophoresis gels. Note
that this is the only method available if you perform band matching on your
image (see above).
Elder-Southern. This and the point-to-point semi-log method are especially
useful for describing band migration in static-field electrophoresis gels. At
least three standard points are required to use this method.
Linear. This method of least-squares polynomial fits is useful for modeling
pulsed-field electrophoresis gels.
Quadratic. At least three standard points are required to use this method of
least-squares polynomial fits.
Cubic. At least four standard points are required to use this method of least-
squares polynomial fits.
Logistic. At least five standard points are required to use this method of
nonlinear least-squares curve fitting.
Cubic-Spline. At least five standard points are required to use this beta-cubic-
spline method.