Google PPC Rates

I am not able to understand the base on which google determines rate per click on a keyword. I got in this dilema because of some observations that i went through.

I find out that for a travel related keyword for which there are around 100 clicks per days on 1st position google is charging 0.20 Cents per click.

While for a flower related keyword on which there is only 1 click per day they are charging $1.30 per click.

On what basis these rates are determined??

 

It's market driven - i.e it depends on what Adwords users are bidding on the keyword/phrase.

 

...I might add, the same as Overture and the other services.

 

But based on analysis i have given it sometime sounds too much senseless to bid for certain keywords. I mean if u r getting just one hit in a day the rate per click should be less rather higher than one getting 100 clicks per day.

 

Again, it's market driven. How many potential clicks a day you get does not come into the equation.