(2) The MDPC code is defined by a parity-check matrix H [member of] [F.sub.2n] of the i-th row [h.sub.i] With overwhelming probability, this matrix is of full rank, and the rightmost r x r block is always invertible after possibly swapping a few columns.
In this section, we first construct the QD-MDPC code by compacting the public-key matrix of the MDPC code using a quasi-dyadic matrix.
To allow the QD code to resist a DCA, we use the MDPC code to improve the QD code, and the QD-MDPC code then generates a parity-che[c.sub.k] matrix H that has a larger density.
The MDPC code is compared with the LDPC code, and has a higher error correction capability.
 Baldi M, Santini P, Chiaraluce F., "Soft McEliece: MDPC code-based McEliece cryptosystems with very compact keys through real-valued intentional errors," in Proc.
where SCORE is the C-SPAN score; the first independent variable, RealGdpGrowth, is the same as the one used in Curry and Morris; the next six independent variables are the same as the ones used in Simonton and in Curry and Morris; and the MDPC (military deaths per capita) rank corresponds to American military combat deaths divided by the population during a president's tenure, with rank 1 meaning the most military combat deaths per capita.
In other words, once our MDPC variable is added, the effect of GDP growth on presidential greatness falls.
Our MDPC variable, even though statistically significant, would be relatively unimportant if a one-rank difference in deaths per capita had little effect on the presidential ranking.
The statistical significance of the MDPC rank variable remains strong, although diminished, when the top two presidents (Franklin Delano Roosevelt and Abraham Lincoln) are removed from the sample.