USING THE STATS PROGRAM


 The easiest way to use the program is to dedicate a directory to hold
all your variable files. (A variable file is a file of real numbers.)
Then run the program by typing "/public/bin/stats" in an xterm window. If
/public/bin is in your path (you can check with "echo $PATH") you can
run the program by typing just "stats". 
***If you run the program in the directory containing your variable files,
the command "vars" will list the correct files; (this behavior can be changed
by putting an edited copy of statsrc in the directory from which you run
the program.)
In the sample below, I temporarily made a directory named "junk" to hold
some files and ran the program in that directory.

A sample session:

_________________________________________________________________________
linux63:friedman/junk> /public/bin/stats
*******************WELCOME TO STATS*******************
*****(All programming and code by Chas. Friedman)*****
******************************************************

          Type ? to see a list of commands.

cmd>vars
data1
data2
data2-2
data3
data3.bak
data4
data5
data6
data7
data8
VARIABLES LOADED: 
cmd>load data5
cmd>count data5
number of data values = 1000 [variable: data5]
min = 0.002533
max = 0.997375
cmd>fcount data5
FREQUENCY COUNT FOR data5
number of data values in [0.002533, 0.102017] = 115 [freq = 0.115000]
number of data values in (0.102017, 0.201501] = 100 [freq = 0.100000] 
number of data values in (0.201501, 0.300986] = 92 [freq = 0.092000] 
number of data values in (0.300986, 0.400470] = 85 [freq = 0.085000] 
number of data values in (0.400470, 0.499954] = 102 [freq = 0.102000] 
number of data values in (0.499954, 0.599438] = 103 [freq = 0.103000] 
number of data values in (0.599438, 0.698922] = 111 [freq = 0.111000] 
number of data values in (0.698922, 0.798407] = 116 [freq = 0.116000] 
number of data values in (0.798407, 0.897891] = 93 [freq = 0.093000] 
number of data values in (0.897891, 0.997375] = 82 [freq = 0.082000] 
cmd>mean data5
mean = 0.494395 [variable: data5]

A confidence interval for the mean with confidence coeff 1-a 
is given by 0.494395 +- z_{a/2}(0.009059) 
where z_{a/2) = xval_n 1-a/2.

A 90 % confidence interval is: 0.494395 +- 0.014893

A 95 % confidence interval is: 0.494395 +- 0.017747

A 99 % confidence interval is: 0.494395 +- 0.023327
cmd>f_n 2  
f_n(2.0000) = 0.9772
cmd>xval_n .9772
xval_n(p=0.977200)=1.999000
cmd>quit
linux63:friedman/junk>
_________________________________________________________________________
The following is the output of the ? command:

The following are implemented commands:

   ?                        for help

   !! command               to execute shell command

   sh                       to start a shell

   edit               start editor (on file if given)

   vars                     to see directory of variables for stats program

   load variable            to load a variable file into the program

   unload variable          to unload a variable from the program

   mean variable            find mean of (loaded) variable
			    Also computes some *confidence intervals*

   means var1 var2          find means and sample stdev of var1, var2
                            and some *confidence intervals* for the diff
			    of the means

   var variable             find variance and st.dev. of (loaded) variable

   svar variable            find sample variance and sample st.dev. 
                            of (loaded) variable
			    Also computes some *confidence intervals*

   count variable           for count of (loaded) variable

   count a b variable       for count of (loaded) variable in (a,b]

   fcount variable          for frequency count of (loaded) variable

   nth variable n           exhibit entry n of (loaded) variable

   fact n                   to compute n!

   perm n r                 to compute (n)(n-1)...(n-r+1) [permutations]

   comb n r                 to compute (n)(n-1)...(n-r+1)/r! [combinations]

   bin x n p                to compute the pf of the binomial distribution
                            [pf: comb(n,x)p^x(1-p)^{n-x}]

   f_bin x n p              to compute the cdf of the binomial distribution
                            [the sum of bin i n p for i=0,...,x]

   negbin x r p             to compute the pf of the negative binomial dist.
                            [pf: comb(x-1,r-1)p^r(1-p)^{x-r} 
			    when r=1 this is the geometric distribution]

   f_negbin x r p           to compute the cdf of the negative binomial dist.
                            [the sum of negbin i r p for i=r,...,x]
  
   hgeom x r N n            to compute the pf of the hypergeometric dist.
                            [pf: comb(r,x)comb(N-r,n-x)/comb(N,n)]

   f_hgeom x r N n          to compute the cdf of the hypergeometric dist.
                            [the sum of hgeom i r N n for i=0,...,x]

   poisson x l              to compute the pf of the Poisson distribution
                            [pf: e^{-l}l^x/x!]

   f_poisson x l            to compute the cdf of the Poisson distribution
                            [the sum of poisson i l for i=0,...,x]

   gamma x                  to compute gamma function of x. 
                            [gamma(k)=(k-1)!]
   f_gamma x l r            to compute cdf of gamma distribution
                            [pdf:(l^r/gamma(r))x^{r-1}e^{-lx)]

   f_chisqr x k             to compute cdf of chisqr distribution
                            [pdf:((1/2)^{k/2}/gamma(k/2))x^{k/2-1)e^{-x/2)] 

   f_n x                    to compute the cumulative normal distribution of x
                            [standard pdf - mean 0, variance 1]

   xval_n p                 to compute 1st x for which f_n(x)=p

   xval_t p k               to compute 1st x for which f_t(x,k)=p

   xval_f p m n             to compute 1st x for which f_f(x,m,n)=p

   xval_chisqr p k          to compute 1st x for which f_chisqr(x,k)=p

   xval_bin P n p           to compute 1st x for which f_bin(x,n,p) >= P

   xval_negbin P r p        to compute 1st x for which f_negbin(x,r,p) >= P

   xval_hgeom P r N n       to compute 1st x for which f_hgeom(x,r,N,n) >= P

   xval_poisson P l         to compute 1st x for which f_poisson(x,l) >= P
   
   f_f x m n                to compute cdf of F distribution
    [pdf:(G((m+n)/2)/(G(m/2)G(n/2))(m/n)^{m/2)x^{(m-2)/2}(1+mx/n)^{-(m+n)/2}
    where G=gamma]

   f_t x k                  to compute cdf of t distribution
    [pdf:(G((k+1)/2)/G(k/2)sqrt(k*pi))(1+x^2/k)^{-(k+1)/2} where G=gamma]

   regress                  to do a linear least squares regression and fit   
                            var_0 = b_0 + b_1(var_1) + ...+ b_n(var_n)

   anova1                   to do a one way anova

   chisqr var1 var2         to compute the chisquare statistic for goodness
                            of fit to a multinomial distribution. var1 should
                            be a file of nonnegative integers ni, var2 should
			    be a file containing probabilities pi. The
			    chisquare statistic is the sum of the terms
			    (ni-n*pi)^2/n*pi where n is the sum of the ni.

   quit                     to exit the program