Module: Statsample::SPSS
- Defined in:
- lib/statsample/converter/spss.rb
Class Method Summary collapse
-
.tetrachoric_correlation_matrix(ds) ⇒ Object
Export a SPSS Matrix with tetrachoric correlations .
Class Method Details
.tetrachoric_correlation_matrix(ds) ⇒ Object
Export a SPSS Matrix with tetrachoric correlations .
Use:
ds=Daru::DataFrame.from_excel("my_data.xls")
puts Statsample::SPSS.tetrachoric_correlation_matrix(ds)
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 |
# File 'lib/statsample/converter/spss.rb', line 9 def tetrachoric_correlation_matrix(ds) dsv=ds.dup_only_valid # Delete all vectors doesn't have variation dsv.vectors.each { |f| if dsv[f].factors.size==1 dsv.delete_vector(f) else dsv[f]=dsv[f].dichotomize end } tcm=Statsample::Bivariate.tetrachoric_correlation_matrix(dsv) n=dsv.vectors.to_a.collect {|f| sprintf("%d",dsv[f].size) } meanlist=dsv.vectors.to_a.collect{|f| sprintf("%0.3f", dsv[f].mean) } stddevlist=dsv.vectors.to_a.collect{|f| sprintf("%0.3f", dsv[f].sd) } out=<<-HEREDOC MATRIX DATA VARIABLES=ROWTYPE_ #{dsv.fields.join(",")}. BEGIN DATA N #{n.join(" ")} MEAN #{meanlist.join(" ")} STDDEV #{stddevlist.join(" ")} HEREDOC tcm.row_size.times {|i| out +="CORR " (i+1).times {|j| out+=sprintf("%0.3f",tcm[i,j])+" " } out +="\n" } out+="END DATA.\nEXECUTE.\n" end |