Well, the model description is not being translated.
You initialize them with N_(), shouldn't it be with _()?

(...)
    case M_HQC:
    descrip = N_("Hannan-Quinn Information Criterion");
    val = pmod->criterion[C_HQC];
    statname = "$hqc";
    break;
    default:
    dummy_call();
    return;
    }

    sprintf(vname, "%s_%d", statname + 1, pmod->ID);

    blurb = g_strdup_printf(_("Statistic from model %d\n"
                  "%s (value = %g)\n"
                  "Name (max. 15 characters):"),
                pmod->ID, descrip, val);