calculate kurtosis in matlab and minitab but not same answer

it my data

 0.53767	-1.30769	-1.34989	-0.20497
 1.83389	-0.43359	 3.03492	-0.12414
-2.25885	 0.34262	 0.72540	 1.48970
 0.86217	 3.57840	-0.06305	 1.40903
 0.31877	 2.76944	 0.71474	 1.41719

Kmatlab=kurtosis(x(:,2))=1.4069

but in minitab 
kurtosis(x(:,2))=-2.37

??????

Answer 1

[dpb]

Looks like Minitab uses the bias-corrected estimator with the "-3" convention applied --

K>> kurtosis(x(:,2),0)
ans =
          0.63
K>> 3-2.37
ans =
          0.63
K>> 0.63-3
ans =
         -2.37
K>> 

With the default for the optional flag default in MATLAB (==1), then you get the result you got.

See the 'Algorithms' section of the documentation for full details.

With only 5 observations and that the estimator of K uses sum((x-xBar).^4), the random variation in the estimator is quite high and I wouldn't put much faith at all i such a statistic as far as making any judgement from it.