Can anyone run a database and maybe provide some stats?

On a long losing runs of favourites, do they become poorer and poorer value? Was thinking the other day that with the amount of people/systems that chase favs, after a loosing run of even 3-4 favs, would the odds on offer versus the true value of the favourite start to be affected?

What got me thinking about this was we were at the casino the other day, and there had been a run of 5 reds, so naturally, everybody started throwing all there money on the black because supposedly it was due to win. As it turned out, there were another 4 reds in a row, which quickly bankrupted a number of the players at the table who kept backing it.

Any thoughts on this, do you think this would apply to racing as well, and could we use this to our advantage in laying favs to lose?