E1 function

Absolute Model Efficiency (E1)

It estimates the E1 model efficiency using absolute differences.

E1(data = NULL, obs, pred, tidy = FALSE, na.rm = TRUE)

Arguments

• data: (Optional) argument to call an existing data frame containing the data.
• obs: Vector with observed values (numeric).
• pred: Vector with predicted values (numeric).
• tidy: Logical operator (TRUE/FALSE) to decide the type of return. TRUE returns a data.frame, FALSE returns a list; Default : FALSE.
• na.rm: Logic argument to remove rows with missing values (NA). Default is na.rm = TRUE.

Returns

an object of class numeric within a list (if tidy = FALSE) or within a data frame (if tidy = TRUE).

Details

The E1 is a type of model efficiency that modifies the Nash-Sutcliffe model efficiency by using absolute residuals instead of squared residuals. The E1 is used to overcome the NSE over-sensitivity to extreme values caused by the used of squared residuals. For the formula and more details, see online-documentation

Examples

set.seed(1)
X <- rnorm(n = 100, mean = 0, sd = 10)
Y <- rnorm(n = 100, mean = 0, sd = 9)
E1(obs = X, pred = Y)

References

Legates & McCabe (1999). Evaluating the use of “goodness-of-fit” measures in hydrologic and hydroclimatic model validation. Water Resour. Res. tools:::Rd_expr_doi("10.1029/1998WR900018")