From 0d2a5b096c226e4e64c8dcf23e932d35f63ebde6 Mon Sep 17 00:00:00 2001
From: Christoph Ruegg <git@cdrnet.ch>
Date: Sat, 16 Nov 2013 15:51:37 +0100
Subject: [PATCH] GoodnessOfFit: docs, add R value

---
 src/Numerics/GoodnessOfFit.cs | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/Numerics/GoodnessOfFit.cs b/src/Numerics/GoodnessOfFit.cs
index 1908d8ec..e675773a 100644
--- a/src/Numerics/GoodnessOfFit.cs
+++ b/src/Numerics/GoodnessOfFit.cs
@@ -34,15 +34,28 @@ namespace MathNet.Numerics
     public static class GoodnessOfFit
     {
         /// <summary>
-        /// Calculated the R-Squared value given modelled and observed values
+        /// Calculated the R-Squared value, also known as coefficient of determination,
+        /// given modelled and observed values
         /// </summary>
         /// <param name="modelledValues">The values expected from the modelled</param>
         /// <param name="observedValues">The actual data set values obtained</param>
-        /// <returns></returns>
+        /// <returns>Squared Person product-momentum correlation coefficient.</returns>
         public static double RSquared(IEnumerable<double> modelledValues, IEnumerable<double> observedValues)
         {
             var corr = Correlation.Pearson(modelledValues, observedValues);
             return corr * corr;
         }
+
+        /// <summary>
+        /// Calculated the R value, also known as linear correlation coefficient,
+        /// given modelled and observed values
+        /// </summary>
+        /// <param name="modelledValues">The values expected from the modelled</param>
+        /// <param name="observedValues">The actual data set values obtained</param>
+        /// <returns>Person product-momentum correlation coefficient.</returns>
+        public static double R(IEnumerable<double> modelledValues, IEnumerable<double> observedValues)
+        {
+            return Correlation.Pearson(modelledValues, observedValues);
+        }
     }
 }