1 crj 716 - prof. kaci. 2 abany prot. 68 cathol. 38 yes 7671 no 8 41 221 12167 9179...
TRANSCRIPT
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Measures of Association:
Nominal / Ordinal Variables
1- Lambda () and Gamma ()
CRJ 716 - Prof. Kaci
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Measures of Association: Lambda Impact of Religion on Abortion Attitudes
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
Jew None Other Total
144 109 10 62 21 346Total
167 people support Abortion for any reason 179 people oppose Abortion for any reason We would make less errors if we guessed “No” every
time: We would make 167 errors.
CRJ 716 - Prof. Kaci
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If we knew each person’s religion we would improve our guess:
Religion Guess Educated Errors
Protestant No 68
Catholic No 38
Jewish Yes 2
None Yes 21
Other Yes 9
Total 138CRJ 716 - Prof.
Kaci
Measures of Association: Lambda Impact of Religion on Abortion Attitudes
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
Jew None Other Total
144 109 10 62 21 346Total
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Religion Guess Educated Errors
Total 138
17.4% reduced error when religion is a known factor in guessing attitudes on Abortion for any reason.
Measures of Association: Lambda Impact of Religion on Abortion Attitudes
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
Jew None Other Total
144 109 10 62 21 346Total
CRJ 716 - Prof. Kaci
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Measures of Association: Lambda Impact of Religion on Abortion Attitudes
CRJ 716 - Prof. Kaci
Measure of Association Lambda ()
Type of Variable Nominal x NominalNominal x Ordinal
Values (Strength)
Range from 0 to 1
0 No Association
1 Perfect Association
Direction Not Applicable
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Measures of Association: Gamma ()
CRJ 716 - Prof. Kaci
Measure of Association Gamma ()
Type of Variable Ordinal x Ordinal
Values (Strength)
Range from -1 to +1
-1 Perfect Negative Association
0 No Association
+1 Perfect Positive Association
Direction
+indicates Positive AssociationAs one variable increases (decreases), so too does the other (variables move in the same direction)
- indicates Negative AssociationAs one variable increases, the other decreases (variables move in the opposite direction)
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Significance Tests:
Nominal / Ordinal Variables
2- Chi-square (X2)
CRJ 716 - Prof. Kaci
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Measures of Association: Chi-square Impact of Religion on Abortion Attitudes
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
48.3%
51.7%
Jew None Other Total
144 109 10 62 21 346Total
CRJ 716 - Prof. Kaci
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Measures of Association: Chi-square Calculating Chi-square
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
48.3%
51.7%
Jew None Other Total
144 109 10 62 21 346Total
70 53
74 565 30
5 32
10
11
Expected:
144 * .483
144 * .517 CRJ 716 - Prof.
Kaci
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Measures of Association: Chi-square Calculating Chi-square
ABANY Prot.
68
Cathol.
38Yes76 71No
8 41
2 21
12 167
9 179
48.3%
51.7%
Jew None Other Total
144 109 10 62 21 346Total
70 53
74 56
5 305 32
10
11Expecte
d:
-2 -15
2 153 11
-3 -11
2
-2
Difference between: Observed - Expected
CRJ 716 - Prof. Kaci
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Measures of Association: Chi-square Calculating Chi-square
ABANY Prot. Cathol.
Jew None Other Total
70 53
74 56
5 305 32
10
11
Expected:
-2 -15
2 153 11
-3 -11
2
-2
Difference between: Observed - Expected
0.06 4.25
0.05 4.02
1.8 4.031.8 3.78
0.4
0.36
(-2)2 / 70
22 / 74
Square the difference and divide by the EXPECTED values
Square the difference and divide by the EXPECTED values
CRJ 716 - Prof. Kaci
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Measures of Association: Chi-square Calculating Chi-square
0.06 4.25
0.05 4.02
1.8 4.031.8 3.78
0.4
0.36
Add these values up. The sum is the Chi-square value.
Add these values up. The sum is the Chi-square value.
0.05 4.25 4.02 1.8 1.8 4.03 3.78 0.4 0.36 20.55
CRJ 716 - Prof. Kaci
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Degrees of Freedom DF = (row - 1) * (column -
1) = = (2-1) * (5-1) = 1 * 4 df = 4
Measures of Association: Chi-square Calculating Chi-square
CRJ 716 - Prof. Kaci
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Where: X2 Chi-square O Observed Values E Expected Values under Ho
Measures of Association: Chi-square Chi-square Formula
CRJ 716 - Prof. Kaci
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Questions???
CRJ 716 - Prof. Kaci