There were many instances where budgets were slashed due to factors besides actual ratings--time period downgrades first and foremost-- and there was no discernable ratings erosion that immediately resulted from them. As for ratings growth--in daytime in particular, there's rarely been a cause-and-effect that a bigger budget caused a ratings increase. Even in the case of ABC PYRAMID the show was improving once it moved to 2 PM before the jackpot was doubled.
Sure, tournaments with large payoffs occasionally spiked numbers--the JOKER's run between 77 and 80 where each ensuing tournament's grand prize was improved upon are perhaps the best example--but the belief that the bigger the payoff the bigger the audience is essentially a myth, and Lord knows I spent far too much time analyzing ratings patterns to prove that point to superiors who felt strongly about keeping budgets in line to overrule otherwise eager producers who still believed the myth,