How do identical slot titles vary return %?

Let's say I go to Vegas, and play the "Red Dwarf" video slot. (Not a real slot, but wouldn't it be fun?)
I play it at 1¢ denomination, 25 (max) lines.

I come home, go to a local casino, and play the identical title, "Red Dwarf" slot, 1¢ denom, 25 (max) lines.

Are my overall theoretical return percentages going to be the same?

If they are not, what is altered within the game in Vegas and my local casino to make the payback % different in each machine?

• Symbol weighting?
• Paytable differences?
• Bonus game payouts different?
• Somehow use progressive jackpots to change payback %?
• Some other way?

How can the same "Red Dwarf" slot be loose in one location, and tight in another?

They may be the same.

If they are different, the cause can be all / any of the above.

And it's impossible to know what, if anything, is different in the two machines.


Note: The same is true for two "identical" machines sitting next to each other.

Quote: Dween

How can the same "Red Dwarf" slot be loose in one location, and tight in another?

For the same reason that a Game King single line JoB VP can have a 9/6 pay table in one place and an 8/5 one in another: manufacturers offer customizable pay tables and payoffs; the casinos customize the machines according to their own criteria.

Dween,
Most machines either come with several options for payback percentage or can be ordered with different payback percentages. The casino operator chooses an option with a theoretical hold they are comfortable with. The differences in hold between the various return percentages can be a result of any of the examples you mentioned but the operator doesn't choose what gets changed, its incorporated into the program by the manufacturer.

Mark

Another question to add.

If a slot is able to be altered to change the return %, can it be made to pay an exact % amount?

I would think that changing a symbol weighting might make the % shift from say, 91.21% to 91.34%, but what if I wanted exactly 91.25%?
Video poker example: Changing from 9/5 to 8/5 might make the return shift from 94.6% to 91.3%... can the paytable be altered to make the return exactly 92%? Or are casinos stuck with choosing one or the other?

I realize there is a lot of mystery involved in my question, and the slot manufacturers are keeping their secrets closely guarded, so I don't mind some speculation.

On poker and keno, the changes must be made by changing the paytable. These are easy for the player to identify. There may be some exceptions to this, but it would have to be related to a bonus feature of some sort.

On other slot machines, most of the time, the only difference is the symbol weighting. If it were caused by paytable changes, then the player could see this. Occasionally, there are different bonus settings.

It is not uncommon for the manufacturer to make about 10 pay schedules for each game, ranging from about 83% to 98/99%. It is not possible to choose an exact return, the operator must choose from what is given.

Quote: Dween

I would think that changing a symbol weighting might make the % shift from say, 91.21% to 91.34%, but what if I wanted exactly 91.25%?

If an operator was really hard-nosed about it, they could have the manufacturer juggle things to get it where they want it.

That would require new math analysis and gaming testing, etc. All of which cost money that the operator doesn't want to pay.

The simple alternative is, put in 7 machines at 91.21% and 3 at 91.34%. That would bring the average to 91.249%. Would that be acceptable Mr Casino Operator?

Quote: Dween

Let's say I go to Vegas, and play the "Red Dwarf" video slot. ...I go to a local casino, and play the identical, "Red Dwarf".
Are my overall theoretical return percentages going to be the same?

You've changed geography and machines. Let's just start off with the SAME geography: You got two Red Dwarfs sitting side by side in Vegas. Are the innards and the math identical? No, not necessarily, but each machine is subject to the general rules of competition on the Strip and each Red Dwarf has only the chips the manufacturer issues and the Gaming Board approves of.

Now, we change the Geography: You are no longer in Nevada, so the law has changed, but the maker of Red Dwarf aims his sales at Nevada so the machine is probably the same. If in your home state there is less regulation then there will probably be more switching of the innards. Chips that fit The Red Dwarf can be swapped into "Your Machine" with less cost and less rigamarole. That doesn't mean the new owner is inclined to do so, only that he is able to do so. Its quite possible that the newly relocated machine has identical insides and may keep them for awhile. At its next routine maintenance, some non-routine work may get performed to make the machine pay less, but there is no way you are likely to find out about it since neither marketing pressures nor legal pressures create much "sunshine".

In this case, size matters. IGT will only create/alter pay tables for its biggest customers. A small independent casino who wants 5 slot machines will get a hellaofalot less attention than MGM who might order 500 of them. In that case, IGT would probably work with MGM to setup the pay tables and MGM would probably get a say in the design itself.