Choosing Statistical Techniques
Univariate Statistics: Analysis on One Variable | ||||
Level of Measurement | Example Variable | Appropriate Central Tendency Statistics | Appropriate Dispersion Statistics | Appropriate Graphs |
Nominal | Race, Sex, Yes/No Questions | Percentages, Mode | Range | Bar Chart, Pie Chart |
Ordinal | Questions with Likert Response Sets | Percentages, Mode, Median | Range | Bar Chart, Pie Chart |
Interval | Age in years, education years | Mode, Median, Mean | Range, Variance, Standard Deviation | Histogram, Scatterplot, Box plot |
Ratio (we do not have many Ratio variables in Sociology) | Income in dollars and cents | Mode, Median, Mean | Range, Variance, Standard Deviation | Histogram, Scatterplot, Box plot |
Bivariate Statistics: The Relationship between Two Variables | |||
DV Measurement | IV Measurement |
Appropriate Bivariate Analysis | Appropriate Bivariate Graph |
categorical: 1 category |
categorical: 2 categories |
Two Group Proportion Test |
Bar Chart |
categorical: 2-4 categories |
categorical: 2-4 categories |
Crosstab |
Bar Chart |
continuous |
categorical: 1 category |
One Group Means Test |
Line Graph, Box Plot |
continuous | categorical: 2 categories |
Two Group Means Test |
Line Graph, Box Plot |
continuous |
categorical: 2 paired groups |
Matched Group Means Test |
Line Graph, Box Plot |
continuous | categorical: 3+ categories | ANOVA | Line Graph, Box Plot |
continuous | continuous | Pearson Correlation | Scatterplot |
Multivariate Statistics: The Relationship between Three or More Variables (Including Control Variables and One Dependent Variable) * | |||
DV Measurement | IV Variables Measurement |
Control Variables Measurement | Appropriate Bivariate Analysis |
categorical |
categorical |
categorical | Elaboration |
continuous | categorical: 2+ categories | continuous | ANCOVA |
continuous | continuous | continuous | Partial Correlation or Regression |
continuous | multiple continuous variables | multiple continuous variables | Regression |
*We don't usually do graphs for multivariate analyses, with the exception of Partial Correlations and Regression for which you can do a partial scatterplot for every independent variable that you have in your analysis. This plot looks at the relationship between the IV and the DV, controlling for any of the other independent variables or control variables.