This index calculates a value such that a certain fraction of difference between methods will be numerically smaller than this. The TDI is a measure which esentially is a number K such that the interval [-K,K] contains the limits of agreement.
Usage
TDI(y1, y2, p = 0.05, boot = 1000, alpha = 0.05)
Arguments
y1
Measurements by one method.
y2
Measurements by the other method.
p
The fraction of items with differences numerically exceeding the TDI
boot
If numerical, this is the number of bootstraps. If FALSE no confidence interval for the TDI is produced.
alpha
1 - confidende degree.
Value
A list with 3 components. The names of the list are preceeded by the
criterion percentage, i.e. the percentage of the population that the TDI is
devised to catch.
TDI
The numerically computed value for the TDI. If boot is
numeric, a vector of median and a bootstrap c.i. is appended.
TDI
The approximate value of the TDI
Limits of Agreement
Limits of agreement
Details
If boot==FALSE a single number, the TDI is returned.
If boot is a number, the median and the 1-alpha/2 central interval
based on boot resamples are returned too, in a named vector of length 4.
References
LI Lin: Total deviation index for measuring individual agreement with applications in laboratory performance and bioequivalence, Statistics in Medicine, 19, 255-270 (2000)