..
                                       .======.
 Valori percentuali (tp) per         .========| . 
 la distribuzione di Student       .==========|  . 
 con v gradi di liberta'       _.=============|____._
 (area tratteggiata = p)                      tp

                                p
 _______________________________________________________________
   v  .995  .99   .975  .95   .90  .80   .75    .70   .60   .55
 ---------------------------------------------------------------
   1 63.66 31.82 12.71  6.31  3.08 1.376 1.000  .727  .325  .158
   2  9.92  6.96  4.30  2.92  1.89 1.061  .816  .617  .289  .142
   3  5.84  4.54  3.18  2.35  1.64  .978  .765  .584  .277  .137
   4  4.60  3.75  2.78  2.13  1.53  .941  .741  .569  .271  .134
   5  4.03  3.36  2.57  2.02  1.48  .920  .727  .559  .267  .132

   6  3.71  3.14  2.45  1.94  1.44  .906  .718  .553  .265  .131
   7  3.50  3.00  2.36  1.90  1.42  .896  .711  .549  .263  .130
   8  3.36  2.90  2.31  1.86  1.40  .889  .706  .546  .262  .130
   9  3.25  2.82  2.26  1.83  1.38  .883  .703  .543  .261  .129
  10  3.17  2.76  2.23  1.81  1.37  .879  .700  .542  .260  .129

  11  3.11  2.72  2.20  1.80  1.36  .876  .697  .540  .260  .129
  12  3.06  2.68  2.18  1.78  1.36  .873  .695  .539  .259  .128
  13  3.01  2.65  2.16  1.77  1.35  .870  .694  .538  .259  .128
  14  2.98  2.62  2.14  1.76  1.34  .868  .692  .537  .258  .128
  15  2.95  2.60  2.13  1.75  1.34  .866  .691  .536  .258  .128

  16  2.92  2.58  2.12  1.75  1.34  .865  .690  .535  .258  .128
  17  2.90  2.57  2.11  1.74  1.33  .863  .689  .534  .257  .128
  18  2.88  2.55  2.10  1.73  1.33  .862  .688  .534  .257  .127
  19  2.86  2.54  2.09  1.73  1.33  .861  .688  .533  .257  .127
  20  2.84  2.53  2.09  1.72  1.32  .860  .687  .533  .257  .127

 _______________________________________________________________
   v  .995  .99   .975  .95   .90  .80   .75    .70   .60   .55
 ---------------------------------------------------------------

  21  2.83  2.52  2.08  1.72  1.32  .859  .686  .532  .257  .127
  22  2.82  2.51  2.07  1.72  1.32  .858  .686  .532  .256  .127
  23  2.81  2.50  2.07  1.71  1.32  .858  .685  .532  .256  .127
  24  2.80  2.49  2.06  1.71  1.32  .857  .685  .531  .256  .127
  25  2.79  2.48  2.06  1.71  1.32  .856  .684  .531  .256  .127

  26  2.78  2.48  2.06  1.71  1.32  .856  .684  .531  .256  .127
  27  2.77  2.47  2.05  1.70  1.31  .855  .684  .531  .256  .127
  28  2.76  2.47  2.05  1.70  1.31  .855  .683  .530  .256  .127
  29  2.76  2.46  2.04  1.70  1.31  .854  .683  .530  .256  .127
  30  2.75  2.46  2.04  1.70  1.31  .854  .683  .530  .256  .127

  40  2.70  2.42  2.02  1.68  1.30  .851  .681  .529  .255  .126
  60  2.66  2.39  2.00  1.67  1.30  .848  .679  .527  .254  .126
 120  2.62  2.36  1.98  1.66  1.29  .845  .677  .526  .254  .126
  oo  2.58  2.33  1.96  1.645 1.28  .842  .674  .524  .253  .126
 ---------------------------------------------------------------