Changes in vardpoor version 0.2.8
   
    + Corrected calculation in prop_dom_optimal_allocation

Changes in vardpoor version 0.2.6
   
    + Update some descriptions

Changes in vardpoor version 0.2.4
   
    + Bug correction in functiom dom_optimal_allocation.

Changes in vardpoor version 0.2.2
   
    + Made faster functiom dom_optimal_allocation.

Changes in vardpoor version 0.2.0
   
    + Corrected bug in function expvar.