diff options
Diffstat (limited to 'man/din32645.Rd')
| -rw-r--r-- | man/din32645.Rd | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/man/din32645.Rd b/man/din32645.Rd index d251b7c..94486c4 100644 --- a/man/din32645.Rd +++ b/man/din32645.Rd @@ -14,18 +14,33 @@ data(din32645) m <- lm(y ~ x, data=din32645) calplot(m) (prediction <- inverse.predict(m,3500,alpha=0.01)) -# This should give 0.074 according to DIN (cited from the Dintest test data) -round(prediction$Confidence,3) +# This should give 0.07434 according to Dintest test data, as +# collected from Procontrol 3.1 (isomehr GmbH) +round(prediction$Confidence,5) -# According to Dintest, we should get 0.07, but we get 0.0759 -lod(m, alpha = 0.01) +# According to Dintest test data, we should get 0.0698 for the critical value +# (decision limit, "Nachweisgrenze") +(lod <- lod(m, alpha = 0.01, beta = 0.5)) +round(lod$x,4) -# In German, there is the "Erfassungsgrenze", with k = 2, -# and we should get 0.14 according to Dintest -lod(m, k = 2, alpha = 0.01) +# In German, the smallest detectable value is the "Erfassungsgrenze", and we +# should get 0.140 according to Dintest test data, but with chemCal, we can't +# reproduce this, +lod(m, alpha = 0.01, beta = 0.01) +# except by using an equivalent to the approximation +# xD = 2 * Sc / A (Currie 1999, p. 118, or Orange Book, Chapter 18.4.3.7) +lod.approx <- 2 * lod$x +round(lod.approx, digits=3) +# which seems to be the pragmatic definition in DIN 32645, as judging from +# the Dintest test data. -# According to Dintest, we should get 0.21, we get 0.212 -loq(m, alpha = 0.01) +# This accords to the test data from Dintest again, except for the last digit +# of the value cited for Procontrol 3.1 (0.2121) +(loq <- loq(m, alpha = 0.01)) +round(loq$x,4) +# A similar value is obtained using the approximation +# LQ = 3.04 * LC (Currie 1999, p. 120) +3.04 * lod(m,alpha = 0.01, beta = 0.5)$x } \references{ DIN 32645 (equivalent to ISO 11843) @@ -33,5 +48,9 @@ loq(m, alpha = 0.01) Dintest. Plugin for MS Excel for evaluations of calibration data. Written by Georg Schmitt, University of Heidelberg. \url{http://www.rzuser.uni-heidelberg.de/~df6/download/dintest.htm} + + Currie, L. A. (1997) Nomenclature in evaluation of analytical methods including + detection and quantification capabilities (IUPAC Recommendations 1995). + Analytica Chimica Acta 391, 105 - 126. } \keyword{datasets} |