I checked different sources here and here but was still unclear of the response so I am asking. I am thinking of using a Poisson regression for several reasons. One: response is a count, two: data not all numeric three: distribution is not normal. The problem is my data is not aggregated, it is row level and I'm no sure if it's possible to use Poisson (Note: management does not want a logistic regression). If my data must be rearranged to use Poisson, I am unsure which rearrangement to use. I am using R so here is my data frame
## patient hospital data id <- c(123, 234, 456, 567, 678, 789, 890, 901, 1000) # factor year <- c(2015, 2017, 2016, 2017, 2015, 2016, 2016, 2015, 2017) # factor state <- c('NY', 'CA', 'NY', 'MI', 'NV', 'CA', 'CA', 'NY', 'NH') # factor stage <- c('adv','early','adv','stg1','stg2','adv','early','stg1','stg2') # factor age <- c(25, 45, 67, 24, 17, 34, 75, 22, 51) # integer wagesWk <- c(200, 1220.75, 500, 600, 500.5, 1200, 900, 200.5, 400.5) # continuous numStateHosp <- c(45, 100, 54, 100, 37, 90, 71, 92, 52) # integer residence <- c("condo", "shelter", "hospice", "rental", "parents", "condo", "hospice", "parents", "rental") #factor ethnicity <- c('group1','group4','group3','group1','group1','group4','group2','group1','group4') #factor underPhysCare <- c('N','Y','Y','N','Y','N','Y','Y', 'N') #factor df <- data.frame(id, year, state, stage, age, wagesWk, numStateHosp, residence, ethnicity, underPhysCare)
response: count of number patients by year and ethnicity a = year b = ethnicity
therefore: response: countPatients with subscripts ab explanatory variables: year, state, stage, age, wagesWk, ethnicity, underPhysCare
The problem is this is row level data. If I aggregate like this:
num_patients_2015_group1 num_patients_2015_group2 num_patients_2015_group3... num_patients_2016_group1 num_patients_2016_group2 num_patients_2016_group3...
Wouldn't this require multiple Poisson regressions? If so, how do I incorporate my explanatory variables? If Poisson is not a good choice, what other choice can I use? For sure I cant OLS because the normality assumption is violated and I am not allowed to use logistic.
Note: I am not asking for code. I am asking for advice as to how to tackle this problem. Thanx in advance for your help