John, I stand corrected. I really guess I misunderstood what Mark wanted.
I now realize he is an experienced programmer. I'm sure that the correct BASIC routines can be found in a number of books on programming. It seems to me I remember that Apple produced a book quite some time ago and it had in it the method of determining the probability of a Z value. I looked back at some programming I did quite a while back and came up with the following code. I hop that Mark can use it. I know it works in my software but it is only one of about six or seven things the user might want to know when dealing with Z values. Depending on the actual basic language that is used (GWBASIC, QUICKBasic, TurboBasic) this routine should find the probability of a given Z value to at least the fourth decimal place. Of course Mark could scan a copy of the Z table and then put it into a Word document and load that onto the PalmPilot. That way he could quickly refer to the table at any time. I assume Mark can write the code for entering the values. Here is the code, I hope it helps. ZOnly: Mean=0 St.Dev=1 PROMPT$=" Enter the Z value to compare to the MEAN " X$="C" PROMPT$=PROMPT$+PAD$ : PROMPT$=LEFT$(PROMPT$,57) print PROMPT$; input " ",X$ if X$="" OR X$=" " then X$="0" IF X$="-" OR ASC(X$)<45 OR ASC(X$)>57 THEN beep print print " Improper entry. Please try again." print goto GeneralMenu END IF XX=VAL(X$) Y=XX : Y=ABS(Y) IF Y=0 THEN beep : print print " Your entered value must not be zero. Please try again." print input " Depress <Enter> to continue ",rck$ goto GeneralMenu: END IF Y=ABS((Y-Mean)/St.Dev) StandDevAway=Y R=EXP(-(Y^2)/2)/2.5066282746 goto DoCalc ZRawData: print PROMPT$=" Enter the POPULATION MEAN value " X$="C" PROMPT$=PROMPT$+PAD$ : PROMPT$=LEFT$(PROMPT$,57) print PROMPT$; input " ",X$ if X$="" OR X$=" " then X$="0" IF X$="-" OR ASC(X$)<45 OR ASC(X$)>57 THEN beep print print " Improper entry. Please try again." print goto GeneralMenu END IF XX=VAL(X$) Mean=XX St.Dev=-1 WHILE St.Dev<=0 PROMPT$=" Enter the POPULATION STANDARD DEVIATION " X$="C" PROMPT$=PROMPT$+PAD$ : PROMPT$=LEFT$(PROMPT$,57) print PROMPT$; input " ",X$ if VAL(X$)=-999 then goto OnToMenu if X$="" or X$=" " then X$="0" if X$="-" then X$="0" if ASC(X$)<45 or ASC(X$)>57 then X$="0" XX=VAL(X$) IF XX<=0 THEN beep print print " The Standard Deviation must be a positive number." input " Please try again. Depress <Enter> to continue ",rck$ END IF St.Dev=XX WEND AskStxx: St.Dev=St.Dev/(SQR(SSize)) print print " Remember if you are comparing a value to the Mean you may want" print " to enter lower class limit of that value. For instance, if you" print " are interested in a value of 13 you might want to enter 12.5." print PROMPT$=" Enter the value to compare to the MEAN " X$="C" PROMPT$=PROMPT$+PAD$ : PROMPT$=LEFT$(PROMPT$,57) print PROMPT$; input " ",X$ if VAL(X$)=-999 then goto OnToMenu if X$="" or X$=" " then X$=STR$(Mean) if ASC(X$)<45 or ASC(X$)>57 then X$=STR$(Mean) XX=VAL(X$) Y=XX ': Y=ABS(Y) IF Y=Mean THEN beep : print print " Your entered a value that is equal to the Mean. This results" print " in a Z value of 0. goto DoneShowing END IF Interest=Y Y=ABS((Y-Mean)/St.Dev) Top=Interest-Mean StandDevAway=Y R=EXP(-(StandDevAway^2)/2)/2.5066282746 DoCalc: cls : locate 4,1 if Top<0 then StandDevAway=StandDevAway*(-1) if SSize=1 then kk=abs(Top) print " The score entered is "; print using fnform$(kk);abs(Top); print " less than the Mean." end if end if print " For a Z value of "; : print using FORM14$;StandDevAway print print " (y Ordinate at Z) FREQUENCY = "; print using FORM14$; R Z=Y Y=1/(1+.33267*ABS(Y)) T=1-R*(.4361836*Y-.1201676*Y^2+.937298*Y^3) if Z<0 then T=1-T print print " (Area in Larger Portion) PROBABILITY = "; print using FORM14$; T print " (Area in Smaller Portion one-tail = "; print using FORM14$; 1-T print " (Area from Z to Mean one-tail = "; print using FORM14$; .5-(1-T) print " (Area in Smaller Portions two-tail = "; print using FORM14$; (1-T)*2 print DoneShowing: Seems as though this is like re-inventing the wheel and I'm not sure if he helps to understand Z values or probability. GOD BLESS AMERICA Dr. Robert C. Knodt 4949 Samish Way, #31 Bellingham, WA 98226 [EMAIL PROTECTED] "The vocation of every man and woman is to serve other people." -- Tolstoy ================================================================= Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =================================================================