The very first bookmaker to open the book may use some (limited) judgement/analysis to determine the odds. However, the market sorts itself out very quickly. Very little money will trade on those initial odds as the bookmaker will know the market has yet to be properly formed.
In addition, in...
The short answer is it is effectively the punters setting the odds not the bookmakers but that does not really explain the anomaly in the two markets - The only answer I can come up with is it shows there are different punters for each market and they do not entirely agree with each other.
The...