Mean absolute relative difference

In addition, all the paired points (n) including the concentrations measured from the glucose sensor, [glucose] sensor, and the reference glucose measurement, [gluco-se reference, in the correlation plot are used to calculate the overall mean absolute relative difference (MARD). The median MARD is the median relative difference among all the measured values. 

Figure 3.2 The effect of prolonged subcutaneous implantation on biosensor function. Blood glucose values shown in solid circles and glucose sensor values in the continuous lines. The early study (top panel), but not the late study (bottom), shows excellent sensor accuracy and minimal lag between blood glucose and sensed glucose values. MARD (mean absolute relative difference) refers to a sensor accuracy metric. EGA refers to the Clarke error grid analysis accuracy metric.

MAD, mean absolute difference MARD, mean absolute relative difference SD, standard deviation SE, standard error SRE standard relative error. 

The different manufacturers publish their own results in their user manuals. Mean absolute relative difference and bias results from the three manufacturers are shown in Table 5.2. The MARD measures indicates the average difference while the direction of the difference and the bias indicates if the differences are uniform or skewed to positive or negative values. The Clarke error grid analysis for the three manufacturers (Table 5.3) shows a wide difference in A zone results between the... 

CGM system Number of subjects Number of points Mean absolute relative difference Bias... 

Mean absolute difference (MAD) and mean absolute relative difference (MARD) - MAD and MARD quantify the performance in an entire data set within a single value. MARD is a good metric for comparing multiple systems in a single study, but is not useful itself to describe system quality [187, 193]. 

It should be noted that the extracted electron coupling times for NO are smaller than the inverse mode frequency of the low-frequency modes. This is unphysical, as energy transfer into the low-frequency modes cannot occur faster than the motion associated with the modes. Although the absolute values for the friction coefficient obtained with this simple one-dimensional friction model may have limited meaning, the relative difference between step and terrace coefficient clearly indicates a 3-fold stronger couphng of the laser-heated electrons to the adsorbate at the steps relative to the terraces... 

We are now in a position to examine the relative accuracies of a variety of different model chemistries by considering their performance on the G2 molecule set. The following table lists the mean absolute deviation from experiment, the standard deviation and the largest positive and negative deviations from experiment for each model chemistry. The table is divided into two parts the first section lists results for single model chemistries, and the remaining sections present results derived from... 

Fig. 4 Left the mean 1961-1990 monthly temperature for the Ebro catchment. Part (a) shows the annual cycle, each line representing a different RCM simulation and the bold line representing the CRU observed series. The shading represents the 95% confidence interval for the estimate of the observed 30-year sample mean. Part (b) represents the individual monthly model means as an anomaly from the CRU mean with 95% confidence interval superimposed. Part (c) represents the mean absolute annual error for each of the RCMs. Right-, as for left column but for mean precipitation (d) for the Gallego catchment. Model anomalies in parts (e) and (f) are expressed as a percentage relative to the CRU monthly mean. Model numbers correspond to experiments shown in Table 1. Figure from [35]...

Rannestad T, Eikeland OJ, Helland H (2001) The quality of life in women suffering from gynecological disorders is improved by means of hysterectomy. Absolute and relative differences between pre- and postoperative measures. Acta Obstet Gynecol Scand 80 46-51... 

The operation of Eq. (3.3) is illustrated by the results given in Table 2 out of 48 molecules of the cc-pVTZ set. They are listed in order of increasing correlation energy. The first column of the table lists the molecule. The next 6 columns show how many orbitals and orbital pairs of the various types are in each molecule, i.e. the numbers Nl, Nb, Nu, Nlb etc. The seventh column lists the CCSD(T)/triple-zeta correlation energy and the eight column lists the difference between the latter and the prediction by Eq. (3.3). The mean absolute deviation over the entire set of cc-pVTZ data set is 3.14 kcal/mol. For the 18 molecules of the CBS-limit data set it is found to be 1.57 kcal/mol. The maximum absolute deviations for the two data sets are 11.29 kcal/mol and 4.64 kcal/mol, respectively. Since the errors do not increase with the size of the molecule, the errors in the estimates of the individual contributions must fluctuate randomly within any one molecule, i. e. there does not seem to exist a systematic error. The relative accuracy of the predictions increases thus with the size of the system. It should be kept in mind that CCSD(T) results can in fact deviate from full Cl results by amounts comparable to the mean absolute deviation associated with Eq. (3.3). 

A comparison of calculated and experimental anion geometries are provided in Table 5-16. Included are Hartree-Fock models with STO-3G, 3-21G, 6-31G and 6-311+G basis sets, local density models, BP, BLYP, EDFl and B3LYP density functional models and MP2 models, all with 6-31G and 6-311+G basis sets, and MNDO, AMI and PM3 semi-empirical models. Experimental bond lengths are given as ranges established from examination of distances in a selection of different systems, that is, different counterions, and mean absolute errors are relative to the closest experimental distance. 

Better accounts of relative isomer energies are provided by density functional models and by MP2 models. With both 6-3IG and 6-311+G basis sets, BP, EDFl and MP2 models perform best and BLYP models perform worst, although the differences are not great. In terms of mean absolute errors, all models improve upon replacement of the 6-3 IG by the 6-311+G basis set. With some notable exceptions, individual errors also decrease in moving from the 6-31G to 6-311+G basis sets. (A further breakdown of basis set effects is provided in Tables A6-32 to A6-35 in Appendix A6.) The improvements are, however, not great in most cases, and it may be difficult to justify of the extra expense incurred in moving from 6-3IG to the larger basis set. 

Fig. 6.35. The meaning of the relative potential difference across the Cu/CuS04 interface, i.e.. the relative electrode potential, (a) The electrochemical cell corresponding to the relative potential difference, (b) The relative potential difference includes a platinum-copper contact potential and the unknown potential difference across the SHE, apart from the absolute potential difference across the Cu/CuS04 interface.

Table 4-3, with partition coefficient estimation results for 13 aroma compounds partitioned between polyethylene (PE) and ethanol, shows an example of the estimation accuracy one can expect comparing UNIFAC to experimental data and the other partition coefficient estimation methods (Baner, 1999). In order to compare the different estimation methods, average absolute ratios of calculated to experimental values were calculated partitioned substances. When the calculated values are greater than experimental values the calculated value is divided by the experimental value. For calculated values less than the experimental values the inverse ratio is taken. Calculating absolute ratios gives a multiplicative factor indicating the relative differences between values of the experimental and estimated data. A ratio of one means the experimental value is equal to the estimated value. 

Mean absolute errors for IR intensities determined from the standard molecules discussed above are shown in Table 11 for different levels of approximation and a DZP basis. Of course, errors for relative intensities are much smaller. 

Using m = 2 and allowing the adjustable parameter /3 to assume different values for spin-up and spin-down densities, they managed to reduce the mean absolute error (MAE) in the exchange energy by about one third relative to B88. 

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