Re: Re: [chrony-users] question about the values in critical_runs array

[邹林志08963 <ZouLinZhi8963@xxxxxxxxxxx>]

> > I found a formula on the web:

> >

> >   Z = [ r - E(r) ] / sigma

> >

> >   E(r) = ( 2 * n1 * n2 ) / ( n1 + n2 ) + 1,

> >

> >   sigma = sqrt{ [ 2 * n1 * n2 * (  2 * n1 * n2 - n1 - n2 ) ] / [ ( n1 + n2 ) *  ( n1 + n2 ) * ( n1 + n2 -1 ) ] }

> >

> > if Z is z ,  r is runs , E(r) is mu ,  sigma is sqrt(var),   then r = Z * sigma + E(r).

> >

> > should  runs be   "mu + sqrt(var)"  or  "mu -sqrt(var)" ?

> 

> I'm not sure what exactly you are pointing out here, but in our case

> we care only about the lower bound to increase the number of runs when

> it's lower than expected for the number of samples. If the number of

> runs is too high, we don't care.

well, when the formula is " runs = mu - sqrt(var) * Z ", 

the critical_runs will be:

static char critical_runs[] = {

  0,  0,  0,  0,  0,  0,  0,  0,  2,  3,

  3,  3,  4,  4,  5,  5,  5,  6,  6,  7,

  7,  7,  8,  8,  9,  9,  9, 10, 10, 11,

 11, 11, 12, 12, 13, 13, 14, 14, 14, 15,

 15, 16, 16, 17, 17, 18, 18, 18, 19, 19,

 20, 20, 21, 21, 21, 22, 22, 23, 23, 24,

 24, 25, 25, 26, 26, 26, 27, 27, 28, 28,

 29, 29, 30, 30, 30, 31, 31, 32, 32, 33,

 33, 34, 34, 35, 35, 35, 36, 36, 37, 37,

 38, 38, 39, 39, 40, 40, 40, 41, 41, 42,

 42, 43, 43, 44, 44, 45, 45, 46, 46, 46,

 47, 47, 48, 48, 49, 49, 50, 50, 51, 51,

 52, 52, 52, 53, 53, 54, 54, 55, 55, 56

};

and when the formula is " runs = mu + sqrt(var) * Z ", 

the critical_runs will be:

static char critical_runs[] = {

  0,  0,  0,  0,  0,  0,  0,  0,  7,  7,

  8,  9,  9, 10, 10, 11, 12, 12, 13, 13,

 14, 15, 15, 16, 16, 17, 18, 18, 19, 19,

 20, 21, 21, 22, 22, 23, 23, 24, 25, 25,

 26, 26, 27, 27, 28, 28, 29, 30, 30, 31,

 31, 32, 32, 33, 34, 34, 35, 35, 36, 36,

 37, 37, 38, 38, 39, 40, 40, 41, 41, 42,

 42, 43, 43, 44, 45, 45, 46, 46, 47, 47,

 48, 48, 49, 49, 50, 51, 51, 52, 52, 53,

 53, 54, 54, 55, 55, 56, 57, 57, 58, 58,

 59, 59, 60, 60, 61, 61, 62, 62, 63, 64,

 64, 65, 65, 66, 66, 67, 67, 68, 68, 69,

 69, 70, 71, 71, 72, 72, 73, 73, 74, 74

};

I just wonder which one is correct.