mcratio function

Ratio of uncertainty and the variability

Provides measures of variability, uncertainty, and both combined for an mc or an mcnode object.

mcratio(x, pcentral=.5, pvar=.975, punc=.975, na.rm=FALSE)

Examples

data(total)
mcratio(total, na.rm=TRUE)

Arguments

• x: an mc or an mcnode object
• pcentral: the quantile for the central tendency.

.

• pvar: the quantile for the measure of variability.
• punc: the quantile for the measure of uncertainty.
• na.rm: a logical value indicating whether NA values should be stripped before the computation proceeds.

Details

The function evaluates three ratios for each mcnode . Given:

• A: the (100 * pcentral) th percentile of uncertainty (by default the median) for the (100 * pcentral) th percentile of variability
• B: the (100 * pcentral) th percentile of uncertainty for the (100 * pvar) th percentile of variability
• C: the (100 * punc) th percentile of uncertainty for the (100 * pcentral) th percentile of variability
• D: the (100 * punc) th percentile of uncertainty for the (100 * pvar) th percentile of variability

The following ratio are estimated

• Variability Ratio: B / A
• Uncertainty Ratio: C / A
• Overall Uncertainty Ratio: D / A

For multivariate nodes, the statistics are evaluate on each dimension or on statistics according to the corresponding outm value.

Returns

A matrix.

References

Ozkaynak, H., Frey, H.C., Burke, J., Pinder, R.W. (2009) "Analysis of coupled model uncertainties in source-to-dose modeling of human exposures to ambient air pollution: A PM2.5 case study", Atmospheric environment, Volume 43, Issue 9, March 2009, Pages 1641-1649.