My raw data has rows of survey responses, with each column as below (only the first 6 out of 16 are shown).
The survey question Q8 was a multiple-choice question about sentiment toward a brand, with 16 answer choices. The column IDs (M1, M2, M3, ... M16) indicate simply the numeric order in which the choices were made by the participant. So each cell has the same pool of answers to draw from in these 16 columns.
I have pivoted this data, and want to create a symmetric co-occurrence matrix where the row and column represent these 16 answer choices, and where each cell has the # of co-occurrences of each pair of choices. I don't really know where to start and am looking for help. I have attached a .twbx. Thank you!