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I'm calculating the variance for the following set of numbers:

  [1] -19.291289 -11.706371  -2.876207 -14.583748  -8.413912
  [6]  -9.461087 -19.536535 -37.876207 -10.353623 -22.876207
 [11]  15.001170 -22.461125   2.708711 -36.413912 -10.998830
 [16]   1.416252 -18.583748  22.293629  13.538875 -27.583748
 [21] -16.353623 -26.380489 -29.998830  16.485181  10.512047
 [26]  -4.461125  -0.291289 -22.413912 -41.568551 -21.583748
 [31]   3.538875 -16.583748  -8.291289  29.565779  27.565779
 [36]  14.001170  -0.706371  24.708711  41.293629  10.123793
 [41]  -9.407355  10.538913  31.586088 -19.168666  19.708711
 [46]   8.831334  14.708711  22.416252  12.831334  -4.461087
 [51]  -4.407355  46.485181  25.538875  32.831334  -2.461087
 [56]  18.431449  13.512047  12.485181  39.293629   7.831334
 [61]   6.431449  36.416252  -8.487953  21.431449   7.512047
 [66]  24.708711  -6.583748  28.619511 -11.876207  -4.413912
 [71]   3.416252  -4.876207  35.831334 -11.998830  -9.876207
 [76]  28.592645  20.123793  31.878547 -18.291289 -13.706371
 [81]  -2.876207 -15.291289 -11.291289  -6.998830   9.538875
 [86]  -8.413912  -8.514819  -1.168666  17.246416 -17.706371
 [91]  -0.461125   5.416252 -17.121453  31.831334  -7.876207
 [96] -21.461125 -13.876207  33.001170  34.246416   9.416252
[101]   5.512047   5.416252  18.708711  29.831334  23.171006
[106]  -2.413912  29.592645   0.878547  18.123793  -0.291289
[111] -32.998830 -29.407355  25.512047   7.538875   6.708711
[116] -10.461125 -14.998830 -13.291289  15.416252  -2.461125
[121] -29.461125  30.619511  14.416252 -22.536535 -12.434221
[126]  -7.461125   0.586088   9.708711   8.416252 -10.998830
[131]  24.123793   6.123793  22.293629  44.416252 -18.461125
[136]  -0.706371 -16.583748  -3.876207 -10.998830  -7.876207
[141]  21.619511 -30.461125  24.708711  -4.583748   5.831334
[146]  14.416252 -27.291289 -18.434221 -16.407355   9.404583
[151]  17.485181  26.416252   3.123793   1.878547 -12.487953
[156]  23.878547 -18.998830  -2.828994  21.404583 -37.461125
[161]  -1.291289  -3.876207 -31.168666   9.538875 -21.291289
[166] -11.583748 -11.514819 -15.568551  -5.649149 -20.413912
[171] -25.407355   3.538913  19.001170 -11.413912  26.708711
[176]  -8.514819  -8.583748 -24.753584   5.538875  -6.413912
[181] -25.583748 -19.514819  -2.876207 -32.380489  -4.876207
[186]  23.431449 -41.568551 -12.595417 -33.514819  -6.876207
[191]  41.878547 -17.536535 -21.291289   9.538913 -28.568551
[196] -25.461087   6.708711  15.458315  -5.876207  13.293629

I'm calculating the following statistics using R:

max(abs(lastkiderrors))
# [1] 46.48518

var(lastkiderrors)
# [1] 382.7843

sd(lastkiderrors)
# [1] 19.56487

The others are reasonable, but why is the variance so large? What does it mean?

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Variance is the square of standard deviation. If standard deviation $19.56$ is reasonable, a variance of $19.56^2=382.78$ should be reasonable, too, and both mean exactly the same.

Beware that most statistics are in the same units of the original variable (maximum, mean, median, standard deviation, range and so) but variance is the exception because it is that unit squared. Therefore, often its magnitude is several orders of magnitude larger or smaller than other statistics. In fact, this is one of the reasons to use standard deviation for some purposes instead of variance.

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