Mathematica calculates RSquared wrongly?
- To: mathgroup at smc.vnet.net
- Subject: [mg112695] Mathematica calculates RSquared wrongly?
- From: Lawrence Teo <lawrenceteo at yahoo.com>
- Date: Mon, 27 Sep 2010 05:47:13 -0400 (EDT)
sbbBN = {{-0.582258428`, 0.49531889`}, {-2.475512593`,
0.751434565`}, {-1.508540016`, 0.571212292`}, {2.004747546`,
0.187621117`}, {1.139972167`, 0.297735572`}, {-0.724053077`,
0.457858443`}, {-0.830992757`, 0.313642502`}, {-3.830561204`,
0.81639874`}, {-2.357296433`, 0.804397821`}, {0.986610836`,
0.221932888`}, {-0.513640368`, 0.704999208`}, {-1.508540016`,
0.798426867`}};
nlm = NonlinearModelFit[sbbBN, a*x^2 + b*x + c, {a, b, c}, x]
nlm["RSquared"]
The RSquared by Mathematica is 0.963173
Meanwhile, Excel and manual hand calculation show that R^2 should be
equal to 0.7622.
Is Mathematica wrong? Thanks!