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Unformatted text preview: SOCIOLOGY 005 Lecture 5 Analyzing Categoric Data Previous hypothesis tests have focused on the differences between means either between a sample and population or between two or more groups within a sample We can also test hypotheses with nominal and ordinal level data These data are often represented in contingency tables or crosstabulations Analyzing Categoric Data Educational Mobility Ballet  Downward Static Upward  Total++ No  83 785 150  1,018  71.55 83.87 66.96  79.78 ++ Yes  33 151 74  258  28.45 16.13 33.04  20.22 ++ Total  116 936 224  1,276  100.00 100.00 100.00  100.00 Contingency Table Cell  Contains the number of cases have joint values on two variables Marginals  Contain the row totals (row marginals) and column total (column marginals) Totals Independent Variable Outcomes Dependent Variable Outcomes Analyzing Categoric Data Educational Mobility Ballet  Downward Static Upward  Total++ No  83 785 150  1,018  71.55 83.87 66.96  79.78 ++ Yes  33 151 74  258  28.45 16.13 33.04  20.22 ++ Total  116 936 224  1,276  100.00 100.00 100.00  100.00 Contingency Table Column Percentages Statistical Independence Statistical Independence For Contingency Tables, we say that when two variables are not signifcantly related to each other they are statistically independent In order to determine i two variables are independent, we need to calculate expected values or each cell and calculate a chisquare score or the table Expected values are hypothetical values which represent what a cell count would be i the two variables were statistically independent, that is, unrelated The ChiSquared score is used to test the null hypothesis Analyzing Categoric Data Educational Mobility Ballet  Downward Static Upward  Total++ No  83 785 150  1,018   ++ Yes  33 151 74  258   ++ Total  116 936 224  1,276   To calculate the expected value or each cell, we use the ollowing equation: f ij = ( f i )( f j ) N 92.55 746.75 178.79 23.45 189.25 45.29 (1018)(116) 1276 (1018)(936) 1276 (1018)(224) 1276 (258)(224) 1276 (258)(936) 1276 (258)(116) 1276 Analyzing Categoric Data Once we calculate expected values or each cell, we need to calculate a chisquared statistics in order to test the null hypothesis o statistical independence !...
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This note was uploaded on 10/23/2011 for the course SOC 10 taught by Professor Dunn during the Spring '10 term at UC Riverside.
 Spring '10
 dunn
 Sociology

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