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I am trying to run a Zero-Inflated Negative Binomial Count Model on some data containing the number of campaign visits by a politician by county. (Log Liklihood tests indicate Negative Binomial is correct, Vuong test suggests Zero-Inflated, though that could be thrown off by the fact that my Zero-Inflated model is clearly not converging.) I am using the pscl package in R. The problem is that when I run

Call:
zeroinfl(formula = Sanders_Adjacent_Clinton_Visit ~ Relative_Divisiveness + Obama_General_Percent_12 + 
    Percent_Over_65 + Percent_F + Percent_White + Percent_HS + Per_Capita_Income + 
    Poverty_Rate + MRP_Ideology_Mean + Swing_State, data = Unity_Data, dist = "negbin")

Pearson residuals:
     Min       1Q   Median       3Q      Max 
-0.96406 -0.24339 -0.11744 -0.03183 16.21356 

Count model coefficients (negbin with log link):
                           Estimate Std. Error z value Pr(>|z|)
(Intercept)              -1.216e+01         NA      NA       NA
Relative_Divisiveness    -3.831e-01         NA      NA       NA
Obama_General_Percent_12  1.904e+00         NA      NA       NA
Percent_Over_65          -4.848e-02         NA      NA       NA
Percent_F                 1.737e-01         NA      NA       NA
Percent_White             2.980e+00         NA      NA       NA
Percent_HS               -3.563e-02         NA      NA       NA
Per_Capita_Income         7.413e-05         NA      NA       NA
Poverty_Rate             -2.273e-02         NA      NA       NA
MRP_Ideology_Mean        -8.316e-01         NA      NA       NA
Swing_State               1.580e+00         NA      NA       NA
Log(theta)                9.595e+00         NA      NA       NA

Zero-inflation model coefficients (binomial with logit link):
                           Estimate Std. Error z value Pr(>|z|)
(Intercept)              -1.024e+02         NA      NA       NA
Relative_Divisiveness    -3.265e+00         NA      NA       NA
Obama_General_Percent_12 -2.300e+01         NA      NA       NA
Percent_Over_65          -7.768e-02         NA      NA       NA
Percent_F                 2.873e+00         NA      NA       NA
Percent_White             5.156e+00         NA      NA       NA
Percent_HS               -5.097e-01         NA      NA       NA
Per_Capita_Income         2.831e-04         NA      NA       NA
Poverty_Rate              1.391e-02         NA      NA       NA
MRP_Ideology_Mean        -2.569e+00         NA      NA       NA
Swing_State               5.075e-01         NA      NA       NA

Theta = 14696.9932 
Number of iterations in BFGS optimization: 94 
Log-likelihood: -596.5 on 23 Df

Obviously, all of those NA's are less then helpful to me. Any advice would be greatly appreciated! I'm pretty novice at R, StackOverflow, and Statistics, but trying to learn. I'm trying to provide everything needed for the minimal reproducible example, but I don't see anywhere to share my actual data... so if that's something you need in order to answer the question, let me know where I can put it!

SPTS
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  • is this link relevant? https://stackoverflow.com/a/16395909/13513328 – Waldi Jul 10 '20 at 20:46
  • Hi, Waldi! I did look at that before, but I don't think it is relevant. That appears to be about removing NA's from the data being analyzed, not solving my convergence issues (I could be convinced I'm wrong about this, I read it pretty closely but, as I said, I'm pretty new to this!) For what it's worth, I don't have any NAs in my data (at least, not in the variables I'm using) – SPTS Jul 13 '20 at 15:04

0 Answers0