title: facet grid of multiple barplots containing group means
body: <p>I have a dataframe with variables Group (demented, nondemented), sex (M, F) and Age.Group ( (60,70], (70,80], (80,90], (90,100] ) and MMSE (a continuous numerical variable representing a &quot;score&quot; on an assessment). I want to create a bar graph with a bar for each group (demented versus non demented) and the group mean on the y-axis. I then want to create a facet grid so there are 8 separate bar charts, one for M and one for F in each age group. Can't figure out how to get a bar graph in ggplot to have a different variable on the y-axis. Would appreciate any tips!</p>