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https://www.youtube.com/watch?v=yLF45x70A3o  with test for overdisperion:
Package AER
Package pscl
first test for overdisperion -> if not: Possion, If yes :zeroinfl function or glm.nb or Hurdle


https://www.youtube.com/watch?v=aVdxv21kMF8
with test for overdisperion:

package = "pscl"


## data
data("bioChemists", package = "pscl")
## without inflation
## ("art ~ ." is "art ~ fem + mar + kid5 + phd + ment")
fm_pois <- glm(art ~ ., data = bioChemists, family = poisson)
fm_qpois <- glm(art ~ ., data = bioChemists, family = quasipoisson)
fm_nb <- MASS::glm.nb(art ~ ., data = bioChemists)
## with simple inflation (no regressors for zero component)
fm_zip <- zeroinfl(art ~ . | 1, data = bioChemists)
fm_zinb <- zeroinfl(art ~ . | 1, data = bioChemists, dist = "negbin")
## inflation with regressors
## ("art ~ . | ." is "art ~ fem + mar + kid5 + phd + ment | fem + mar + kid5 + phd + ment")
fm_zip2 <- zeroinfl(art ~ . | ., data = bioChemists)
fm_zinb2 <- zeroinfl(art ~ . | ., data = bioChemists, dist = "negbin")