Neither of these means was significantly different from that for all core genes (0.099, SE = 0.002; P = 0.41 and 0.84, respectively), indicating that recombination did not have a strong influence on this metric of positive selection.
This was codified in Orr's QTL sign test [ 20], which compares the distribution of direction of QTL effects to a random expectation, as a quantitative genetic metric of directional selection.
However, even assuming that dN > dS is a good metric of positive selection, there are at least two reasons why it may be hard to detect an arms race using such data from RNA viruses.
Of course, the Ka/Ks ratio is a very rough metric of positive selection and new protein function could arise by neutral evolution, even via very few amino acid substitutions [ 61].
Use of length versus girth as metric for selection in gillnet fisheries and girth as further distinction between discrete population types Appendix S3.
Is Ka / Ks an appropriate metric for selection pressure on amino acid substitutions, in the presence of other selection pressures acting only at the RNA level (such as selection for exonic splicing enhancers)?
Therefore, based on the minmax criterion which can ensure that all nodes' packet error rates are not extremely high, the metric of the BANCO selection can be given by begin{array}{*{20}l} M_{k}^{BANCO} &= min_{stackrel{scriptstyle i in {mathrm V}_{mathrm node}} {i ne j}} left{M_{k,i}^{BANCO} right} end{array} (20).
By executing the first (lines 2 to 7) and the second (lines 8 to 15) part of Algorithm 2, we could determine the metric of the second relay selection (line 5 in Algorithm 2) and select the second relay (lines 8 to 15 in Algorithm 2) respectively.
First, we can standardize the selection gradients by the standard deviation of spawning date; a standardized selection gradient provides a useful metric to compare the strength of selection among traits and populations (Lande and Arnold 1983; Arnold and Wade 1984).
To avoid having a big CHEV value, we take the log of CHEV as a final selection metric of CHs.
