what is the zeroinfl variable in poisson glm why is the poisson glm in error what is factor zero why does zeroinfl pscl error how does zeroinfl work what is zeroinfl why does zeroinfl work in poisson glm analysis zero factor pscl what counts zero does zeroinfl work in poisson glm what to look for in zeroinfl what factor level is zero how does zeroinfl work in statistics what is zero factor mean how does an all zero factor count in poisson glm work how many zeros to zero infl what level of data is zero infl what is zeroinfl and zeropscl does zeroinfl work in poisson glm what is zeroinfl used for in statistics