Error when performing imbalance - Cem

24 Oct 2018

Hello,

I’ve just begun to use CEM package for R.

My database has 657 obs., no missing values, treatment is a dummy (1 is
treated, 0 is untreated).

This is a summary of my variables:

...
  is.data.frame(NHq1) 
[1] TRUE

...

...
  summary(NHq1) 
   Treatment          Female            Size           Pcoffee

 Min.   :0.0000   Min.   :0.0000   Min.   : 0.084   Min.   :0.008333

 1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.: 1.400   1st Qu.:0.333333

 Median :1.0000   Median :0.0000   Median : 3.000   Median :0.600000

 Mean   :0.6591   Mean   :0.1492   Mean   : 6.072   Mean   :0.585863

 3rd Qu.:1.0000   3rd Qu.:0.0000   3rd Qu.: 7.500   3rd Qu.:0.833333

 Max.   :1.0000   Max.   :1.0000   Max.   :64.000   Max.   :1.000000

      Age5           Age5.15           Age15         Productivity

 Min.   :0.0000   Min.   :0.0000   Min.   :0.0000   Min.   :  16.43

 1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.: 720.00

 Median :0.0000   Median :1.0000   Median :0.0000   Median :1271.89

 Mean   :0.2907   Mean   :0.6058   Mean   :0.1035   Mean   :1393.20

 3rd Qu.:1.0000   3rd Qu.:1.0000   3rd Qu.:0.0000   3rd Qu.:1920.00

 Max.   :1.0000   Max.   :1.0000   Max.   :1.0000   Max.   :7119.05

   Familiness         Poverty           GDP

 Min.   :0.00000   Min.   : 0.00   Min.   : 2653

 1st Qu.:0.05096   1st Qu.: 8.60   1st Qu.: 2671

 Median :0.43421   Median :23.90   Median : 6516

 Mean   :0.46640   Mean   :33.57   Mean   : 5914

 3rd Qu.:0.85000   3rd Qu.:55.00   3rd Qu.: 7526

 Max.   :1.00000   Max.   :99.60   Max.   :12069

I’m trying to calculate the imbalance but I get the following error:

...
  todrop <- c("Productivity",
"Treatment", "GDP") 
...
  imbalance(group=Treatment, data=NHq1, drop=todrop)

Error in t1 > 0 & t2 > 0 : non-conformable arrays

I could implement the cem function without problems, but if I include
eval.imbalance = TRUE in the argument, I get the same error:

...
  mat1 <- cem(treatment = "Treatment",
data=NHq1, drop=c("Productivity", "GDP"), keep.all = TRUE,
eval.imbalance = TRUE) 
Error in t1 > 0 & t2 > 0 : non-conformable arrays

...
  mat1 <- cem(treatment = "Treatment",
data=NHq1, drop=c("Productivity", "GDP"), keep.all = TRUE) 
...
  mat1 
           G0  G1

All       224 433

Matched    35  52

Unmatched 189 381

Do you have any idea of what could be wrong with the database?

Thank you in advance for your help.

Best Regards,

*Sara Benetti* | *Researcher *
*INCAE Business School  <https://www.incae.edu/en>*