The common space function extracts latent dimensions from a collection of roll call scaling results using the procedure outlined in Poole (1998) and Poole (2005) .
common_space(nom_list, id = NULL, dims = 2, minscale = 5, polarity = NULL)A list of nomObject results from the
wnominate package. The number of estimated dimensions in
each nomObject should be greater than or equal to
dims.
Column name in the nomObjects' legislators
data frames providing a unique legislator ID. If not specified
row names will be used.
The number of dimensions to estimate.
The minimum number of W-NOMINATE scores a
legislator must have to be used for the latent dimension
estimates. Common space scores for legislators with fewer than
minscale scores will be derived from the estimated
dimensions.
A vector of ID's of length dims of
legislators who should have relatively positive scores on the
corresponding dimension. If only one ID is provided, it will be
recycled for all dimensions.
A list of class common space containing:
legislators A data frame of legislator coordinates
blackbox A list of blackbox results
nom_list The provided list of wnominate results
Poole KT (1998).
“Recovering a Basic Space From a Set of Issue Scales.”
American Journal of Political Science, 42(3), 954--993.
ISSN 0092-5853, doi:10.2307/2991737
, https://www.jstor.org/stable/2991737.
Poole KT (2005).
Spatial Models of Parliamentary Voting, Analytical Methods for Social Research.
Cambridge University Press.
doi:10.1017/CBO9780511614644
.
blackbox, which this function is basically
a wrapper around