Type: | Package |
Title: | Metrics and Plots for Model Evaluation |
Version: | 1.0.0 |
Maintainer: | Kristin Piikki <kristin.piikki@slu.se> |
Description: | Functions for metrics and plots for model evaluation. Based on vectors of observed and predicted values. Method: Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg (2021). <doi:10.1111/SUM.12694>. |
Depends: | R (≥ 4.0.0) |
Suggests: | roxygen2, knitr, markdown |
License: | MIT + file LICENSE |
Encoding: | UTF-8 |
LazyData: | true |
RoxygenNote: | 7.1.1 |
VignetteBuilder: | knitr |
NeedsCompilation: | no |
Packaged: | 2021-01-09 16:51:10 UTC; piikki |
Author: | Kristin Piikki [aut, cre, cph], Johanna Wetterlind [aut, cph], Mats Soderstrom [aut, cph], Bo Stenberg [aut, cph] |
Repository: | CRAN |
Date/Publication: | 2021-01-13 15:30:02 UTC |
ac
Description
Calculates the Agreement coefficient (AC) from observed and predicted values.
Usage
ac(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: larger is better.
Value
Agreement coefficient (AC).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Willmott, C. J. (1984). On the evaluation of model performance in physical geography. In Spatial statistics and models. Springer, Dordrecht, Netherlands.
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
ac(o=obs, p=pred)
adjr2
Description
Calculates the Adjusted R2 (adjr2) from observed values, predicted values and the number of model parameters.
Usage
adjr2(o, p, k)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
k |
A number. The number of parameters in the model. Note that k includes the intercept, so for example, k is 2 for a linear regression model. |
Details
Interpretation: larger is better. Adjusted R2 (adjr2) punishes complexity of models; a larger number of parameters (k) means a smaller adjr2 value.
Value
Adjusted R2 (adjr2)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
adjr2(o=obs, p=pred, k=2)
aic
Description
Calculates the Akaike information criterion (AIC) from observed values, predicted values, the number of observations and the number of model parameters.
Usage
aic(o, p, k)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
k |
A number. The number of parameters in the model. Note that k includes the intercept, so for example, k is 2 for a linear regression model. |
Details
Interpretation: smaller is better. Akaike information criterion (AIC) punishes complexity of models; a larger number of parameters (k) means a larger AIC value. As it is sensitive to the number of samples, AIC cannot easily be compared between datasets of different sizes.
Value
Akaike information criterion (AIC)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
aic(o=obs, p=pred, k=2)
allmetrics
Description
Calculates 31 different validation metrics from observed values and predicted values. For the calculation of some metrics also the number of model parameters are used.
Usage
allmetrics(o, p, k)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
k |
A number. The number of parameters in the model. Note that k includes the intercept, so for example, k is 2 for a linear regression model. |
Details
See respective functions.
Value
A data.frame with all validation metrics for which functions are defined in this package.
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
allmetrics(o=obs, p=pred, k=2)
e
Description
Calculates the Nash-Sutcliffe modelling efficiency (E) from observed and predicted values.
Usage
e(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: a value of 1 means that all predicted values are equal to the observed values. A value of 0 means that the predictions explain as much of the variation in the observed values as the mean of the observed values does. A negative value means that the predictions are less accurate the mean of the observed values.
Value
Nash-Sutcliffe modelling efficiency (E).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Nash, J. E., & Sutcliffe, J. V. (1970). River flow forecasting through conceptual models part I. A discussion of principles. Journal of hydrology, 10(3), 282-290.
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Wilks D. S. (2011) Statistical Methods in the Atmospheric Sciences, Academic Press, Oxford, UK.
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
e(o=obs, p=pred)
iqr
Description
Calculates the Inter-quartile range (IQR) from a vector of observed values.
Usage
iqr(o)
Arguments
o |
A numeric vector. Observed values. |
Details
The inter-quartile range (IQR) is the difference between the 75-percentile and the 25-percentile of the observed values.
Value
Inter-quartile range (IQR).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
iqr(o=obs)
lc
Description
Calculates the Lack of correlation (LC) from observed and predicted values.
Usage
lc(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Lack of correlation (LC)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Gauch H. G., Hwang J. G., & Fick G. W. 2003. Model evaluation by comparison of model based predictions and measured values. Agronomy Journal, 95(6), 1442-1446.
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
lc(o=obs, p=pred)
lccc
Description
Calculates Lin's concordance correlation coefficient (LCCC) from observed and predicted values.
Usage
lccc(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: Lin's concordance correlation coefficient (LCCC) can take values between -1 and 1. LCCC-values close to 1 indicate a strong concordance between predicted and observed values, while LCCC-values near -1 indicate a strong discordance. LCCC-values close to 0 indicate no concordance. In a plot of predicted values versus observed values, an LCCC-value of 1 means that the all data points are on the 1.1-line.
Value
Lin's concordance correlation coefficient (LCCC).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Lawrence, I., & Lin, K. (1989). A concordance correlation coefficient to evaluate reproducibility. Biometrics, 255-268.
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
lccc(o=obs, p=pred)
mad
Description
Calculates the Median absolute deviation (MAD) from observed and predicted values.
Usage
mad(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Median absolute deviation (MAD)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mad(o=obs, p=pred)
mae
Description
Calculates the Mean absolute error (MAE) from observed and predicted values.
Usage
mae(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. Similar to RMSE but less sensitive to large errors.
Value
Mean absolute error (MAE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mae(o=obs, p=pred)
mape
Description
Calculates the Mean absolute percentage error (MAPE) from observed and predicted values.
Usage
mape(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Mean absolute percentage error (MAPE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mape(o=obs, p=pred)
mare
Description
Calculates the Median absolute relative error (MARE) from observed and predicted values.
Usage
mare(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Median absolute relative error (MARE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mare(o=obs, p=pred)
mde
Description
Calculates the Median error (MdE) from observed and predicted values.
Usage
mde(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. Similar to mean error (bias) but less sensitive to large errors. Sometimes called bias.
Value
Median error (MdE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mde(o=obs, p=pred)
mdse
Description
Calculates the Median squared error (MdSE) from observed and predicted values.
Usage
mdse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Median squared error (MSE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mdse(o=obs, p=pred)
me
Description
Calculates the Mean error (ME) from observed and predicted values.
Usage
me(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. Sometimes called bias.
Value
Mean error (ME).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
me(o=obs, p=pred)
msdr
Description
Calculates the Mean squared deviation ratio (msdr) from observed and predicted values.
Usage
msdr(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: closer to 1 is better. Sometimes called standardised squared predictor error (SSPE) or scaled root mean squared error (SRMSE).
Value
Mean squared deviation ratio (msdr)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Voltz, M., & Webster, R. (1990). A comparison of kriging, cubic splines and classification for predicting soil properties from sample information. Journal of soil Science, 41(3), 473-490. (there called: standardized square deviation).
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
msdr(o=obs, p=pred)
mse
Description
Calculates the Mean squared error (MSE) from observed and predicted values.
Usage
mse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. This metric is sometimes called mean squared deviation (MSD or RMSD2).
Value
Mean squared error (MSE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
mse(o=obs, p=pred)
nmse
Description
Calculates the Normalized mean squared error (NMSE) from observed and predicted values.
Usage
nmse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Normalized mean squared error (NMSE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Park S. J., Vlek P. L. G. 2002. Environmental correlation of three-dimensional soil spatial variability: a comparison of three adaptive techniques. Geoderma, 109(1-2), 117-140.
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
nmse(o=obs, p=pred)
nrmse
Description
Calculates the Normalised RMSE (NRMSE) from observed and predicted values.
Usage
nrmse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. Normalised RMSE (NRMSE) is computed as the RMSE divided by the mean of the observed valeus. NRMSE is sometimes called Relative RMSE (rRMSE) or Root mean square standardized (RMSS).
Value
Normalised RMSE (NRMSE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
nrmse(o=obs, p=pred)
nu
Description
Calculates the Non-unity slope (NU) from observed and predicted values.
Usage
nu(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: closer to 1 is better.
Value
Non-unity slope (NU)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
nu(o=obs, p=pred)
precision
Description
Calculates the Precision from observed and predicted values.
Usage
precision(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Precision
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
precision(o=obs, p=pred)
r
Description
Calculates the Pearson product moment correlation coefficient (r) from observed and predicted values.
Usage
r(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: larger absolute value is better.
Value
Pearson product moment correlation coefficient (r).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
r(o=obs, p=pred)
r2
Description
Calculates the Coefficient of determination (R2) from observed and predicted values.
Usage
r2(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: larger is better.
Value
Coefficient of determination (R2)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
r2(o=obs, p=pred)
rmdse
Description
Calculates the Root median squared error (RMdSE) from observed and predicted values.
Usage
rmdse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Root median squared error (RMdSE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
rmdse(o=obs, p=pred)
rmse
Description
Calculates the Root mean square error (RMSE) from observed and predicted values.
Usage
rmse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better. RMSE is sometimes abbreviated RMS, RMSD or RMSEP. A smaller value means a smaller error. RMSE is similar to mean absolute error (MAE), median absolute deviation (MAD) and root median squared error (RmdSE) but is more sensitive to large errors.
Value
Root mean square error (RMSE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
rmse(o=obs, p=pred)
rpd
Description
Calculates the Ratio of performance to deviation (RPD) from observed and predicted values.
Usage
rpd(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: larger is better.
Value
Ratio of performance to deviation (RPD).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom & Bo Stenberg kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
rpd(o=obs, p=pred)
rpiq
Description
Calculates the Ratio of interquartile to RMSE (RPIQ) from observed and predicted values.
Usage
rpiq(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: Smaller is better.
Value
Ratio of interquartile to RMSE (RPIQ)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom & Bo Stenberg kristin.piikki@slu.se
References
Bellon-Maurel V., Fernandez-Ahumada E., Palagos B., Roger J. M., McBratney, A. 2010. Critical review of chemometric indicators commonly used for assessing the quality of the prediction of soil attributes by NIR spectroscopy. TrAC Trends in Analytical Chemistry, 29(9), 1073-1081.
Piikki K., Wetterlind J., Soderstrom M. Stenberg B. Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management, in press.
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
rpiq(o=obs, p=pred)
sde
Description
Calculates the Standard deviation of the error (SDE) from observed and predicted values.
Usage
sde(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Standard deviation of the error (SDE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
sde(o=obs, p=pred)
skew
Description
Calculates the Skewness of residuals from observed and predicted values.
Usage
skew(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Skewness of residuals.
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
skew(o=obs, p=pred)
smape
Description
Calculates the Symmetrical mean percentage error (SMAPE) from observed and predicted values.
Usage
smape(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Symmetrical mean percentage error (SMAPE)
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
References
Forkuor G., Hounkpatin O. K., Welp G., Thiel, M. 2017. High resolution mapping of soil properties using remote sensing variables in south-western Burkina Faso: a comparison of machine learning and multiple linear regression models. PloS one, 12(1), e0170478.
Piikki K., Wetterlind J., Soderstrom M., Stenberg B. (2021). Perspectives on validation in digital soil mapping of continuous attributes. A review. Soil Use and Management. doi: 10.1111/sum.12694
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
smape(o=obs, p=pred)
sse
Description
Calculates the sum of squares for error (SSE) from observed and predicted values.
Usage
sse(o, p)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
Details
Interpretation: smaller is better.
Value
Sum of squares for error (SSE).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 2, 4, 5, 6, 8, 7, 10)
sse(o=obs, p=pred)
sst
Description
Calculates the Total sums of squares (SST) from a vector of observed values.
Usage
sst(o)
Arguments
o |
A numeric vector. Observed values. |
Details
Interpretation: smaller is better.
Value
Total sums of squares (SST).
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
sst(o=obs)
valplot
Description
Plots predicted values versus observed values in a coordinate system with the same range of both axes.
Usage
valplot(
o,
p,
main = NA,
sub = NA,
xlab = "Observed value",
ylab = "Predicted value"
)
Arguments
o |
A numeric vector. Observed values. |
p |
A numeric vector. Predicted values. |
main |
A character value. The main title of the plot. |
sub |
A character value. The subtitle of the plot. |
xlab |
A character value. The x axis label. |
ylab |
A character value. The y axis label. |
Details
Circles represent the data, dashed line represents observed = predicted and solid line represents an
Value
A scatter plot of observed and predicted values.
Author(s)
Kristin Piikki, Johanna Wetterlind, Mats Soderstrom and Bo Stenberg, E-mail: kristin.piikki@slu.se
Examples
obs<-c(1:10)
pred<-c(1, 1 ,3, 5, 4, 5, 6, 8, 11, 10)
t1='Measured variable (unit)'
evalue<-round(e(o=obs, p=pred),2)
maevalue<-round(mae(o=obs, p=pred),1)
t2=paste('E = ', evalue, '; MAE = ', maevalue, ' units')
valplot(o=obs, p=pred, main=t1, sub=t2)