/* Example code for finding (standard) normal probabilities in SAS */

OPTIONS pagesize=50 linesize=64; 
/* (setting the page margins) */

/* The command PROBNORM computes normal probabilities */

/* It computes the probability that a standard normal r.v. is less than (or equal to) */
/* a certain value.  So SAS gives us P(Z < value), whereas Table IV in the book gives */
/* us P(0 < Z < value) */

/* Suppose our random variable Z is standard normal */

/* Let's answer the following questions which were given in class */
/* 1. What is the probability Z is between 0 and 1.24? */
/* 2. What is the probability Z is greater than 1.24?  */
/* 3. What is the probability Z is less than 1.24?  */
/* 4. What is the probability Z is between -0.54 and 0? */
/* 5. What is the probability Z is less than -0.54? */
/* 6. What is the probability Z is between -1.75 and -0.79? */
/* 7. What is the probability Z is between -0.79 and 1.16? */

/* This SAS program will give us the answers to all these questions in an instant */
/* I will label the answers to the 7 questions as normp1, normp2, ... , normp7. */

/*  What if X is normal with mean 266 and standard deviation 16 (like the pregnancy */
/* example in class)?  If you're clever, you can let SAS standardize for you, */
/* as the eighth example here will show: */
/* 8. What is the probability X is between 260 and 280? */

data norm;

normp1 = probnorm(1.24) - probnorm(0);

normp2 = 1 - probnorm(1.24);

normp3 = probnorm(1.24);

normp4 = probnorm(0) - probnorm(-0.54);

normp5 = probnorm(-0.54);

normp6 = probnorm(-0.79) - probnorm(-1.75);

normp7 = probnorm(1.16) - probnorm(-0.79);

normp8 = probnorm((280-266)/16) - probnorm((260-266)/16);

run;

proc print data=norm;
title 'Normal Probabilities';
run;

/* After we input this program into the program editor and do "Run"->"Submit" */
/* Then the results print in the Output window */

/* Compare to the results we got in class using the tables */

/* The difference is:  SAS can do these for any values of Z */