Description Usage Arguments Value Author(s) References
Test for Conditional Independence of Xcovariate Distributions from Treatment Selection within Given, Adjacent PS Bins. The second step in Supervised Propensity Scoring analyses is to verify that baseline Xcovariates have the same distribution, regardless of treatment, within each fitted PS bin.
1  SPSbalan(envir, dframe, trtm, yvar, qbin, xvar, faclev = 3)

envir 
The local control environment 
dframe 
Name of augmented data.frame written to the appn="" argument of SPSlogit(). 
trtm 
Name of the twolevel treatment factor variable. 
yvar 
The outcome variable. 
qbin 
Name of variable containing bin numbers. 
xvar 
Name of one baseline covariate X variable used in the SPSlogit() PS model. 
faclev 
Maximum number of different numerical values an Xcovariate can assume without automatically being converted into a "factor" variable; faclev=1 causes a binary indicator to be treated as a continuous variable determining a proportion. 
An output list object of class SPSbalan. The first four are returned with a continuous xvariable. The next 4 are used if it is a factor variable.
aovdiffANOVA output for marginal test.
form2Formula for differences in X due to bins and to treatment nested within bins.
bindiffANOVA output for the nested within bin model.
df3Output data.frame containing 3 variables: Xcovariate, treatment and bin.
factabMarginal table of counts by Xfactor level and treatment.
tabThreeway table of counts by Xfactor level, treatment and bin.
cumchiCumulative ChiSquare statistic for interaction in the threeway, nested table.
cumdfDegrees ofFreedom for the Cumulative ChiSquared.
Bob Obenchain <[email protected]>
Cochran WG. (1968) The effectiveness of adjustment by subclassification in removing bias in observational studies. Biometrics 24: 205213.
Obenchain RL. (2011) USPSinR.pdf USPS Rpackage vignette, 40 pages.
Rosenbaum PR, Rubin RB. (1983) The Central Role of the Propensity Score in Observational Studies for Causal Effects. Biometrika 70: 4155.
Rosenbaum PR, Rubin DB. (1984) Reducing Bias in Observational Studies Using Subclassification on a Propensity Score. J Amer Stat Assoc 79: 516524.
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