10  COM X[103,22],M[19,19],U[19,19],Q[20],V[20],P[78]
30  COM M$[60],N$[72]
40  COM N,K,N8,K8,N9,K9,Q9,Q7,Q5,Q4,Q3,Q2,Q1
45  COM I3,I4,U9,X$[20]
50  REM:12MAY74
52  REM:EXPLAIN CTAB,MTAB
90  DIM C$[12],E$[4]
1000  PRINT "EXPLANATION OF 'CTAB' AND 'MTAB':"
1005  PRINT 
1010  PRINT "     CTAB PROVIDES A CROSS-TABULATION OR 2-WAY FREQUENCY DISTRI-"
1020  PRINT "BUTION OF CATEGORICAL VARIABLES X AND Y, OR OF QUANTITATIVE VARIABLES"
1030  PRINT "X AND Y THAT CAN BE PUT INTO FREQUENCY CLASSES DURING EXECUTION OF THE"
1040  PRINT "COMMAND.  Y IS THE 'VERTICAL' OR 'ROW' VARIABLE, CORRESPONDING TO"
1050  PRINT "THE 'DEPENDENT VARIABLE' OF SIMPLE REGRESSION.  X IS THE 'HORIZONTAL'"
1060  PRINT "OR 'COLUMN VARIABLE', CORRESPONDING TO THE 'INDEPENDENT' VARIABLE"
1070  PRINT "OF SIMPLE REGRESSION."
1080  GOSUB 9020
1090  PRINT "     IN THE PRINTED TABLE X CAN HAVE A MAXIMUM OF 9 CATEGORIES AND"
1100  PRINT "Y CAN HAVE A MAXIMUM OF 21.  IF X IS CODED IN ADVANCE AS AN INTEGER"
1110  PRINT "IN THE RANGE 1 TO 9, AND Y AS AN INTEGER IN THE RANGE 1 TO 21, THEN"
1120  PRINT "NO EXPLICIT CHOICE OF CLASS INTERVALS NEED BE MADE DURING EXECUTION."
1130  PRINT "OTHERWISE, TAKE THE OPTION OF DEFINING CLASS INTERVALS; THE PROMPTS"
1140  PRINT "ARE DETAILED AT LEVEL 1 AND SHOULD BE SELF-EXPLANATORY.  IF YOU"
1150  PRINT "DO DEFINE CLASS INTERVALS, YOU WILL BE GIVEN THE OPTION OF PRINTING OUT"
1160  PRINT "YOUR 'DECODED' INTERVALS UNDERNEATH THE JOINT FREQUENCY TABLE."
1170  GOSUB 9020
1180  PRINT "     CTAB ALSO GIVES THE OPTION OF PRINTING OUT THE CONDITIONAL"
1190  PRINT "DISTRIBUTION OF Y GIVEN X IN PERCENTAGE FORM--THAT IS, PERCENTS THAT"
1200  PRINT "SUM TO 100 VERTICALLY.  IF YOU WANT PERCENTS IN THE OPPOSITE DIRECTION"
1210  PRINT "RE-EXECUTE THE COMMAND WITH THE VARIABLES INTERCHANGED."
1220  PRINT 
1230  PRINT "     YOU SHOULD BECOME FAMILIAR WITH CTAB BEFORE USING MTAB."
1240  PRINT "WITH BOTH CTAB AND MTAB YOU WILL GET THE BEST RESULTS IN TABLE PRINTOUT"
1250  PRINT "IF YOU HAVE NAMED YOUR VARIABLES UPON THEIR ORIGINAL ENTRY INTO IDA."
1260  PRINT "IF YOU HAVE LOTS OF VARIABLES, YOU MAY PREFER TO USE THE ALTERNATIVE"
1270  PRINT "ENTRY COMMAND 'ENTS', WHICH PERMITS VARIABLES TO BE NAMED ACCORDING"
1280  PRINT "TO THEIR COLUMN IN THE IDA DATA MATRIX."
1290  GOSUB 9020
1300  PRINT "     MTAB MAKES IT POSSIBLE TO TABULATE THE MEANS OF A VARIABLE Z"
1310  PRINT "ACCORDING TO THE CELLS DEFINED BY X AND Y, WHERE X AND Y ARE THE SAME "
1320  PRINT "AS IN CTAB.  THUS Z IS LIKE THE DEPENDENT VARIABLE IN A MULTIPLE"
1330  PRINT "REGRESSION FOR WHICH THE INDEPENDENT VARIABLES ARE X AND Y."
1340  PRINT "THE COMMAND EXECUTES IN MUCH THE SAME FASHION AS CTAB, BUT IN ADDITION"
1350  PRINT "TO X AND Y, YOU WILL BE PROMPTED TO ENTER Z. YOU WILL BE GIVEN THE"
1360  PRINT "OPTION OF PRINTING OUT A 2-WAY TABLE OF X AND Y PRIOR TO THE PRINTOUT"
1370  PRINT "OF THE TABLE OF MEANS OF Z."
1380  GOSUB 9020
1390  PRINT "     IN ORDER TO PROVIDE FOR A NEAT PRINTOUT OF THE MEANS, THEY ARE"
1400  PRINT "PRINTED OUT IN INTEGER FORMAT 'DDDDD'.  YOU WILL BE PROMPTED ON THE"
1410  PRINT "NECESSARY SCALING BY AN APPROPRIATE POWER OF 10 IN ORDER TO DISPLAY"
1420  PRINT "THIS RESULT WITHOUT LOSING IMPORTANT INFORMATION.  THE POWER"
1430  PRINT "OF 10 YOU CHOOSE IS SUCH THAT THE MEANS IN THEIR ORIGINAL UNITS"
1440  PRINT "WILL, WHEN MULTIPLIED BY 10 TO THAT POWER, GIVE THE NUMBERS"
1450  PRINT "IN THE TABLE.  FOR EXAMPLE, SUPPOSE THAT THE MEANS RANGE FROM ONE"
1460  PRINT "TO 10 MILLION.  IF YOU SPECIFY A POWER OF -3, THEN THESE MEANS WILL"
1470  PRINT "BE MULTIPLIED BY 10E-3 AND ROUNDED TO THE NEAREST INTEGER WHEN PRINTED"
1480  PRINT "OUT IN THE TABLE.  THUS THE MEANS IN THE TABLE WILL BE IN "
1490  PRINT "UNITS OF THOUSANDS.  IF YOU NEED GUIDANCE ON THE SIZE OF YOUR MEANS"
1500  PRINT "USE THE 'IDA' COMMAND 'MEAN' BEFORE EXECUTION OF MTAB."
1510  GOTO 9998
9020  IF P[64]=0 OR P[64]>10 THEN 9180
9030  PRINT "* MORE ?";
9040  ENTER 255,Q8,C$
9050  PRINT 
9070  IF Q8>0 THEN 9130
9080  PRINT "PLEASE RESPOND:"
9090  PRINT "NO,"'10"FOLLOWED BY A CARRIAGE RETURN, ";
9100  PRINT "IF YOU DON'T WANT ANY MORE EXPLANATION"
9110  PRINT "WITH A CARRIAGE RETURN ONLY,"'10"IF YOU WANT MORE EXPLANATION"
9120  GOTO 9030
9130  IF C$="" THEN 9190
9132  IF C$[1,1]="Y" THEN 9190
9140  IF C$[1,1]="N" THEN 9998
9150  IF C$[1,1]="?" THEN 9080
9160  PRINT "INVALID RESPONSE."
9170  GOTO 9080
9180  PRINT 
9190  RETURN 
9990  PRINT "TO USE "E$", REISSUE "E$
9998  CHAIN "$IDA",150
9999  END 
