User guide

Quantity One User Guide
15-28
To remove a band from the quantity standards and omit it from calibration
curve calculations, click on the Remove option. All the information regarding
that band will be deleted from the quantity standards file.
Alternatively, you can select Outlier from the pop-up list. This retains the
information about the band in the calibration file but does not include it when
calculating the calibration curve.
15.3.b The Calibration Curve
Calibration Curve Settings
In the Quantity Standards dialog box, select the method with which the
calibration curve should be calculated. Next to the Interpolation prompt,
choose either Point to Point or Linear Regression.
• Point to Point produces a curve in which each point is connected to the
next, regardless of the shape of the resulting curve.
• Linear Regression (using the method of Least Squares) produces a curve
which is the “best fit” of the values you provided.
Next, indicate whether the curve should be extrapolated. If you choose not to
extrapolate, the highest and lowest values you entered will be the ends of the
curve and you will be unable to calculate the estimated quantity for any
bands that lie outside that range. If you want to extrapolate, you can calculate
a quantity value for any band on the gel. But bands whose quantities are
calculated from the extrapolated region of the curve may be less accurate.
Displaying the Calibration Curve
To display the calibration curve, click on the Show Curve button at the
bottom of the Quantity Standards dialog box. A graph of known quantity
versus measured density will be displayed in a separate window.