Homework 3

Use the SOCR Neuroimaging dataset of visceral pain, irritable bowel syndrome, ulcerative colitis, and Crohn's disease.
  • Problem 1: Investigate the effect of the grouping (Group), separating the 3 cohorts, on the gray matter brain volume (GMV), i.e., you can take group as a categorical variable and the GMV values as the observations. Use the SOCR 1-Way ANOVA applet, or R to carry the calculations. Provide all results and explicitly state your inference.
  • Problem 2: Use 2-way ANOVA (using gender and group as the 2 factors) on the R_insular_cortex volume (insular shape has been reported to be associated with visceral pain, irritable bowel syndrome, and ulcerative colitis). Repeat the analysis using the counterlateral L_insular_cortex volume. Report your findings and interpret the results.
  • Problem 3: Determine a linear model of association between the the response (Total Brain Volume, TBV) and the following predictors (Group, Sex, and Age). Explain your findings and interpret your model results.
  • Problem 4: Do people with larger brains necessarily have bigger hippocampal volumes (e.g., L_hippocampus + R_hippocampus)? Formulate a research hypothesis, propose an appropriate statistical technique, apply the corresponding software tool, and report your findings.

SOCR Resource Visitor number Dinov Email