I am trying to learn how to nest missing values in a data set. My dataset contains the number of calculations (Unnatural, Natural and Total) for the year (2001-2009), month (1-12), gender (M / F) and age group (4 groups).
One of the imputation methods that I am studying is (in voisson) regression imputation.
Say my data looks like this:
Year Month Gender AgeGroup Unnatural Natural Total
569 2006 5 Male 15up 278 820 1098
570 2006 6 Male 15up 273 851 1124
571 2006 7 Male 15up 304 933 1237
572 2006 8 Male 15up 296 1064 1360
573 2006 9 Male 15up 298 899 1197
574 2006 10 Male 15up 271 819 1090
575 2006 11 Male 15up 251 764 1015
576 2006 12 Male 15up 345 792 1137
577 2007 1 Female 0 NA NA NA
578 2007 2 Female 0 NA NA NA
579 2007 3 Female 0 NA NA NA
580 2007 4 Female 0 NA NA NA
581 2007 5 Female 0 NA NA NA
...
After the main GLM regression, 96 cases were deleted due to their absence.
// R, GLM "" (.. ) Total ( - Excel )? , , . , /?
Call:
glm(formula = Total ~ Year + Month + Gender + AgeGroup, family = poisson)
Deviance Residuals:
Min 1Q Median 3Q Max
-13.85467 -1.13541 -0.04279 1.07133 10.33728
Coefficients:
Estimate Std. Error z value Pr(>|z|)
(Intercept) 13.3433865 1.7541626 7.607 2.81e-14 ***
Year -0.0047630 0.0008750 -5.443 5.23e-08 ***
Month 0.0134598 0.0006671 20.178 < 2e-16 ***
GenderMale 0.2265806 0.0046320 48.916 < 2e-16 ***
AgeGroup01-4 -1.4608048 0.0224708 -65.009 < 2e-16 ***
AgeGroup05-14 -1.7247276 0.0250743 -68.785 < 2e-16 ***
AgeGroup15up 2.8062812 0.0100424 279.444 < 2e-16 ***
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
(Dispersion parameter for poisson family taken to be 1)
Null deviance: 403283.7 on 767 degrees of freedom
Residual deviance: 4588.5 on 761 degrees of freedom
(96 observations deleted due to missingness)
AIC: 8986.8
Number of Fisher Scoring iterations: 4