iDine math: 7 = 7.5 and rounding
 

I just noticed today that restaurants listed as earning 7 miles to the $ actually earn 7.5 miles. Apparently the iDine web system can only display integers.

Also, I recently encountered an exception to the formula I use to calculate my expected miles in a spreadsheet:

INT(Total Bill * Earning Rate) = Expected Miles

Example:
$8.88 * 10 = 88.8
INT(88.8) = 88 expected miles, credited as such

Exception:
$24.91 * 7.5 = 186.825
INT(186.825) = 186 but listed on iDine is 187

Based on previous experience with this restaurant, I know 7.5 is the correct rate.

In all other cases they have never rounded up and never used standard rounding (up at .5 and greater, else down). They have alwasy used the greatest integer, i.e., rounding down.

Of course, this could have just changed.

Any thoughts? Anyone else this anal? http://www.flyertalk.com/forum/wink.gif

[This message has been edited by Rut Dog (edited 09-06-2003).]

In looking at my dining rewards, I see the following:

Charge $14.39 Credit 143 Miles

No rounding up. If only I added one cent more to the tip, I would have had another American Airlines mile! I'm really kicking myself for not doing that.

When will be the big lawsuit, so I can get the mile I'm owed?


[This message has been edited by burgerwars (edited 09-06-2003).]

I, too, was curious about those 7 mile places, Rutdog. My instinct would be to round up the tip to the nearest whole dollar rather than get involved with the math.

I do make sure that the net charges are evenly divisible at 5-mile-benefit places though. So, I'm with you on being not forfeiting those partial miles!

I do the same, makes the math easier!


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No thanks, I'm just lurking. Call me the Lurker!

This is really funny, as I never even considered rounding a tip to make the total even for getting that one more mile. http://www.flyertalk.com/forum/biggrin.gif I suppose it makes sense even though we are only talking about a few points.

In any case, I was mainly curious if anyone else had noticed 7 = 7.5, and to see if anyone noticed a different rounding scheme.

Maybe they did change to standard rounding, figuring that some people might actually think the rounding down is unfair and take action! We could all join a class action lawsuite, burgerwars. http://www.flyertalk.com/forum/wink.gif

Heh. I've actually condsidered adding that $0.01 to my tip just to get that extra one mile, but I haven't done it yet. I'm glad to know I'm not the only one who has thought of this. http://www.flyertalk.com/forum/smile.gif

You haven't done it??

[This message has been edited by noname (edited 09-08-2003).]

delete

[This message has been edited by noname (edited 09-08-2003).]

I've wondered if servers have wondered why I've left credit card tips such as $1.47 or $2.03. Or have they run across enough other iDiners that it doesn't faze them anymore? http://www.flyertalk.com/forum/wink.gif

I've noticed a lot of people who have never even heard of iDine use the tip to make the total come out to a whole dollar. Why they do this I have no idea, as at the end of the month the credit card company takes care of adding all the charges together.

Ah - yes - but as an iDiner, I round amounts to the nearest ten cents sometimes, not just the actual dollar. Glad to see servers are used to it though.

OK, just to take this to it's absurb extreme...

First off, assuming they round down (which remains to be seen with future miles postings), you need to tip as follows to get that elusive mile:

7.5 miles/$ is much more complicated. You have to round to multiples of $0.1333..., but in whole cents. And to complicate matters further, the cycle repeats over three times over two dollars.

Forget the theory, just always tip up to one of the following figures, where x = Even Dollars, and y = Odd Dollars:

Of course, you could always tip a little more, to the nearest even dollar.

But you'll kick yourself if you tip to an odd dollar! http://www.flyertalk.com/forum/biggrin.gif

I always round to either leave a 0 or to raise to .50. DC counts each charge as the basis of their rounding so a charge of $10.49 gets 10 and a charge of $10.50 gets 11 - that's the points for the charge. They now participate in iDine so you get 20% or 40% off on certain restaurants. Haven't tried my DC on restaurants that give less but it is listed as 15% not 14% off.

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Ms.DtG