EN_ACD_L4_Bivariate analyses - Copy (1)
Bivariate Analysis Overview
Bivariate analysis involves examining relationships between two variables.
It aims to explain results of one variable (dependent) using another (independent).
Hypothesis testing is used to ensure that observed links are statistically significant.
Hypothesis Testing
Validates relationships are not random, using a calculated value compared to a critical value.
Expressed as a p-value; p-value < 0.05 indicates a significant relationship.
General threshold in Social Sciences is p=0.05; lower in medical research.
Types of Variable Relationships
Qualitative-Qualitative: Analyzed through Chi-square test.
Numeric-Numeric: Correlation coefficient (r).
Qualitative-Numeric: ANOVA or T-test, with T-test used when qualitative has two modalities; ANOVA for more than two modalities.
Chi-square Test
Decision rule: p-value ≤ 0.05 suggests a relationship; p-value > 0.05 indicates independence.
Normal Distribution for Pearson's r
When t > |1.96|, a relationship exists; if t is between -1.96 and +1.96, no relationship.
ANOVA
Measures relationships between numeric and qualitative variables.
Compares means, with significance identified if p-value < 0.05.
Statistical Analysis Parameters
Report specific values depending on the test used (Chi-square, r-value, F statistic).
Statistical tests are critical for inferential statistics in social sciences.
Reporting Analysis Results
Chi-square Report: Significant relationship with Chi-square = 9.90, p-value < .01.
Correlation Report: Strong positive correlation of r = 0.58, p-value < .05.
ANOVA Report: Significant gender differences in car maintenance time: F = 49.89, p-value < .01; Men: M = 3.34, Women: M = 0.76.