Accuracy and Precision of Measurements
Build an alpha-beta-sigma Matrix for Use with the cplot Function
Compute the estimates of betas.
Compute accuracy estimates and maximum likelihood estimates of precisi...
Scatter plot of observations for a pair of devices with calibration cu...
Extracts the estimated measurement errors assuming there is a constant...
Extracts the estimated measurement errors assuming there is no bias an...
Extracts the estimated measurement errors assuming there is a nonconst...
Likelihood ratio test for all betas equalling one.
A modified "pairs" plot with all axes haveing the same range.
Compute maximum likelihood estimates of precision.
Compute squared standard errors for imprecision estimates for the cons...
Compute accuracy estimates and maximum likelihood estimates of precisi...
Compute full information maximum likelihood estimates of accuracy and ...
Draw diagonal line (line of equality) on merror.pairs plots
Computes Grubbs' method of moments estimators of precision for the con...
Computes Grubbs' method of moments estimators of precision for the non...
Computes iterative approximation to mle precision estimates for noncon...
Compute process standard deviation
Compute process variance but with minor error in Jaech Fortran code.
Compute process variance.
Computes the ith iteration for computing the squared imprecision estim...
N>=3 methods are used to measure each of n items. The data are used to estimate simultaneously systematic error (bias) and random error (imprecision). Observed measurements for each method or device are assumed to be linear functions of the unknown true values and the errors are assumed normally distributed. Pairwise calibration curves and plots can be easily generated. Unlike the 'ncb.od' function, the 'omx' function builds a one-factor measurement error model using 'OpenMx' and allows missing values, uses full information maximum likelihood to estimate parameters, and provides both likelihood-based and bootstrapped confidence intervals for all parameters, in addition to Wald-type intervals.