Advertisement
Data Processing Parameters
Quantitative curve fit
Polynomial fit types
156
Thermo Scientific SkanIt
to improve the validity of statistical analyses. Logarithmic transformation
is employed when data dynamics is considerable. This facilitates
mathematical adaptations, that is, curve fitting.
The Conc. logarithmic transformation cannot be selected for the
four-parameter logistic or Log-Logit fit types.
Note If the concentration range of the calibrators is more than
four decades, logarithmic transformation should be used to obtain
more precise curve fitting.
•
Markers - Select whether the means of the measured calibrator replicates
or individual measurements (replicates) are displayed in the curve. The
replicates cannot be selected for point-to-point or cubic spline fit types.
The polynomial fit function is determined as:
y = a + bx + cx
•
n = 1, 2, 3 or 4,
•
a, b, ..., m = coefficients,
•
x = the concentration value, and
•
y = the measured signal.
Derived from the above equation:
•
y = a + bx for the Linear regression (LLS) fit type. The minimum number
of calibrators is two.
Note If only one calibrator is used, then the second point is
assumed to cross the origo (0,0).
It is recommended to use at least three (3) calibrators in order to
raise the quality of the result.
•
y = a + bx + cx
number of calibrators is three.
•
y = a + bx + cx
number of calibrators is four.
•
y = a + bx + cx
minimum number of calibrators is five.
®
®
Software for Varioskan
User Manual
2
n
...mx
, where
2
for the Quadratic polynomial fit type. The minimum
2
3
+ dx
for the Cubic polynomial fit type. The minimum
2
3
4
+ dx
+ ex
for the Quartic polynomial fit type. The
Thermo Fisher Scientific
Hide quick links:
Advertisement
