**Focus on **__Relationships__ between variables - an example
165. PREMARITAL SEX ATTITUDES- FEMALE VALUES IN THE TABLE
Expected Disapproved Disallowed ARE PERCENTS
________Y_________________ 63.
|__1-2___|__3-4___|___5-6_| COMMUNITY SIZE N
X | |
1| 63 5 32 | < 50 19
2| 56 22 22 | 50-99 18
3| 44 35 21 | 100-199 34
4| 45 25 30 | 200-399 20
5|___48___ 26 26 | 400-999 23
6 11 | 33 56 | 1,000-4,999 9
7 0 |___40___ 60 | 5,000-49,999 5
8 0 0 |___100_| > 50,000 2
Totals 58 33 39 130
r = .257 p < .01 (significant -- using Fisher-b)
This example of a table, from a student project, shows us a relationship between
Community Size and Premarital Sexual Attitudes for females. The table was made
with MAPTAB (World Cultures 7(2):2-25, see DW if you want a copy of the Tutorial),
but can be done just as easily in SPSS using files 3 and 7). I want to call your
attention to the asymmetric relationship between the two variables:
If --------X----- (more X) then ---------Y---------------- (more Y)
1. As Community Size increases ---> Approval of Premarital Sex (1-2) drops off and
__drops off quickly above sizes of 1,000__
__to more widespread disapproval (3-4; 5-6)__.
This is a __conditional__ relationship: the converse relationship is not so strong.
If --------X----- (less X) then ---------Y---------------- (less Y)
2. As Community Size decreases ---> disapproval may drop (but not always),
__but below 1,000 tendency is very small__.
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Quick Review of Forms of relationship: (predicate logic)
Root Form: Opposite (Negative)
1. If X then Y (or more Y) 2. If X then not Y (less Y)
Converse (doesnt follow from the root) Opposite of Converse
3. If Y then X (or more X) 4. If Y then not X (less X)
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Each of these distinct statements has an equivalent contrapositive:
Root Form Contrapositive: Contrapositive of Opposite
1. If NOT Y then NOT X (or LESS X) 2. If Y then not X (MORE X)
Contrapositive of Converse Contrapositive of Opposite of Converse
3. If NOT X then NOT Y (or LESS Y) 4. If X then not Y (MORE Y)
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(Note that I stated the converse in the example in contrapositive form, form 3.)
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Take home: JUST GETTING YOUR LOGIC STRAIGHT IS HALF THE BATTLE