15.7.1.3 Overriding Measurement Level

By default, CTABLES uses a variable’s measurement level to decide whether to treat it as categorical or scalar. Variables assigned the nominal or ordinal measurement level are treated as categorical, and scalar variables are treated as scalar.

When PSPP reads data from a file in an external format, such as a text file, variables’ measurement levels are often unknown. If CTABLES runs when a variable has an unknown measurement level, it makes an initial pass through the data to guess measurement levels using the rules described in an earlier section (see Measurement Level). Use the VARIABLE LEVEL command to set or change a variable’s measurement level (see VARIABLE LEVEL).

To treat a variable as categorical or scalar only for one use on CTABLES, add ‘[C]’ or ‘[S]’, respectively, after the variable name. The following example shows the output when variable monthDaysMin1drink is analyzed as scalar (the default for its measurement level) and as categorical:

CTABLES
    /TABLE monthDaysMin1drink BY gender
    /TABLE monthDaysMin1drink [C] BY gender.

		Male	Female
	S3a. GENDER:
	Male	Female
	Mean	Mean
20. On how many of the thirty days in this typical month did you have one or more alcoholic beverages to drink?	7	5
		S3a. GENDER:
		Count	Count
20. On how many of the thirty days in this typical month did you have one or more alcoholic beverages to drink?	None	152	258
1	403	653
2	284	324
3	169	215
4	178	143
5	107	106
6	67	59
7	31	11
8	101	74
9	6	4
10	95	75
11	4	0
12	58	33
13	3	2
14	13	3
15	79	58
16	10	6
17	4	2
18	5	4
19	2	0
20	105	47
21	2	0
22	3	3
23	0	3
24	3	0
25	35	25
26	1	1
27	3	3
28	13	8
29	3	3
Every day	104	43