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Daniele Nicolodi <nicolodi@science.unitn.it>
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1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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Daniele Nicolodi <nicolodi@science.unitn.it>
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2 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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3 % Compute the sample (bias-corrected) skewness.
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Daniele Nicolodi <nicolodi@science.unitn.it>
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4 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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5 % CALL
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Daniele Nicolodi <nicolodi@science.unitn.it>
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6 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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7 % p = Skew(x);
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Daniele Nicolodi <nicolodi@science.unitn.it>
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8 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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9 % VERSION: $Id: Skew.m,v 1.1 2011/02/25 10:04:07 congedo Exp $
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Daniele Nicolodi <nicolodi@science.unitn.it>
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10 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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11 % HISTORY: 25-02-2011 G. Congedo
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Daniele Nicolodi <nicolodi@science.unitn.it>
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12 %
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Daniele Nicolodi <nicolodi@science.unitn.it>
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13 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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Daniele Nicolodi <nicolodi@science.unitn.it>
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14
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Daniele Nicolodi <nicolodi@science.unitn.it>
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15 function s = Skew(x)
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Daniele Nicolodi <nicolodi@science.unitn.it>
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16
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Daniele Nicolodi <nicolodi@science.unitn.it>
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17 n = numel(x);
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Daniele Nicolodi <nicolodi@science.unitn.it>
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18 mu3 = sum((x-mean(x)).^3)/n;
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Daniele Nicolodi <nicolodi@science.unitn.it>
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19 sig = sqrt(sum((x-mean(x)).^2)/n);
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Daniele Nicolodi <nicolodi@science.unitn.it>
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20 s = mu3/(sig)^3;
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Daniele Nicolodi <nicolodi@science.unitn.it>
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21
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Daniele Nicolodi <nicolodi@science.unitn.it>
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22 % Bias correction
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Daniele Nicolodi <nicolodi@science.unitn.it>
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23 s = sqrt(n*(n-1))/(n-2)*s;
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Daniele Nicolodi <nicolodi@science.unitn.it>
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24
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Daniele Nicolodi <nicolodi@science.unitn.it>
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25 end |