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Who said anything about APM only being used by laptops?

Who said anything about APM only being used by laptops?

Posted Apr 5, 2011 16:06 UTC (Tue) by nye (guest, #51576)
In reply to: Who said anything about APM only being used by laptops? by giraffedata
Parent article: Powering down APM

>In the example I gave, the proposer said the electricity savings would pay for the purchase. He was wrong.

You haven't shown that though. All you've pointed out is that in a hypothetical scenario you posit, there are other balancing concerns.

In particular, the scenario you describe is valid only for [a subset of] businesses.


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Who said anything about APM only being used by laptops?

Posted Apr 6, 2011 2:58 UTC (Wed) by giraffedata (subscriber, #1954) [Link]

In the example I gave, the proposer said the electricity savings would pay for the purchase. He was wrong.
You haven't shown that though. All you've pointed out is that in a hypothetical scenario you posit, there are other balancing concerns.

Other balancing concerns? You mean the value of time? That's not a balancing concern, but an intrinsic part of any comparison of an immediate payment versus a series of payments over time. Not considering time in this comparison is like not considering the shipping charge when comparing prices on Ebay.

Incidentally, this example is a true story, from a very ordinary business, as opposed to one operating in a black hole where time has no value.

Who said anything about APM only being used by laptops?

Posted Apr 6, 2011 15:20 UTC (Wed) by nye (guest, #51576) [Link]

>Other balancing concerns? You mean the value of time?
>...
>Incidentally, this example is a true story, from a very ordinary business, as opposed to one operating in a black hole where time has no value.

I honestly have no idea how what you're talking about relates to the value of time. Could you please explain further in words of one syllable?

If it helps, my idea of the value of time is something like this: it takes me X hours to perform task Y; that's X hours I could have spent doing something else and which I'll never get back. Hence, there is a cost to performing task Y.

Who said anything about APM only being used by laptops?

Posted Apr 6, 2011 16:30 UTC (Wed) by giraffedata (subscriber, #1954) [Link]

Not wanting to do a task because it takes time is part of the concept of time having value that I'm talking about. But more basically, it's the fact that a person generally prefers to have something now than to have it later. It's the reason you have to pay interest on a loan. It's the concept behind the business adage, "expense delayed is expense reduced." I think it's an unsettled question among economists exactly what the psychological basis for that is, but I know it involves the limited lifespan of a person, uncertainty which grows the further into the future you look, and the fact that entropy increases with time.

There are myriad ways you can bring this abstract concept into focus in making a business decision by looking at interest you would pay on a loan or income you would make on an investment in pay now vs pay later scenarios, and I tried to do that by describing how my company would end up wealthier by investing money in something other than LCD monitors and continuing to pay, in the future, for the extra electricity for the CRTs. (With all other factors ignored, of course). Even though the total dollar electricity savings exceed the purchase price of the LCD.

But the basic concept is well known to beginning economics and accounting students as "present value." $10 paid a year from now is worth less than $10 paid now. (And there is math to tell you how much less).

Who said anything about APM only being used by laptops?

Posted Apr 11, 2011 11:19 UTC (Mon) by nye (guest, #51576) [Link]

I still remain highly unconvinced that this applies in the given situation in the real world, but if I find the time (as it were) I'll try to do some research into the relevant economic theory.

Thanks for humouring me.

She said she said

Posted Apr 11, 2011 19:07 UTC (Mon) by gvy (guest, #11981) [Link]

> It's the reason you have to pay interest on a loan.
Actually it's not a reason but rather a bait. But then again, given that interest-based loans are forbidden in all of the three monotheistic religions, the kludgery to make this social exploit work looks evil enough. I'm quite happy being free enough not to subscribe to any loans at all.

PS: my first notebook, a Fujitsu-Siemens C6535, still works and APM functions just fine there (suspend, hibernate, poweroff, blank). Wish all of my Thinkpads (A/T/X series) were that durable and dependable.

She said she said

Posted Apr 11, 2011 20:24 UTC (Mon) by nybble41 (subscriber, #55106) [Link]

> > It's the reason you have to pay interest on a loan.
> Actually it's not a reason but rather a bait.

If the interest is bait then it must be bait for the one *issuing* the loan, not the one paying the interest, which seems rather the opposite of what you were implying. (Unless you're arguing that predatory borrowers use the promise of interest to bait traps for unwary lenders? That would be quite a reversal.)

Anyway, giraffedata was correct: time preference is why those who take out loans must pay interest. The present value to the lender of the money loaned today is less than the present value of the same money a year from now, so the borrower must pay some additional amount back (the interest) to make up the difference. A truly interest-free loan would be a net loss to the lender, which makes such loans very rare indeed.

Time preference is also the reason the borrower is *willing* to pay that interest, as the present value to the borrower of the larger amount to be paid back in a year is less than the present value of the amount received today. This is possible because different people have different time preferences, which also vary over time. Those with higher time preferences borrow from those with lower time preferences for mutual benefit.

She said she said

Posted Apr 11, 2011 20:28 UTC (Mon) by giraffedata (subscriber, #1954) [Link]

It's the reason you have to pay interest on a loan.
Actually it's not a reason but rather a bait.

Bait is something that leads someone into a trap -- i.e. misleads the person into doing something he doesn't want to do. What bait are you talking about?

I can assure you that the reason I won't lend you money unless you pay me interest is that I value time. I would have to delay my enjoyment of the things I would spend that money on, and I won't do that voluntarily without compensation. No trap, no bait.

I have long wanted to study ancient usury laws, because if they are what they seem to be, it's hard to imagine people wanting them.

She said she said

Posted Apr 11, 2011 22:48 UTC (Mon) by cmccabe (guest, #60281) [Link]

Firstly, there are more than 3 monotheistic religions. Secondly, Judaism and Christianity don't forbid interest-based loans.

From wikipedia:

> The Hebrew Bible regulates interest taking. Interest can be
> charged to strangers but not between those who are close to
> each other.
>
> Deuteronomy 23:20 Unto a foreigner thou mayest lend upon interest; but
> unto thy brother thou shalt not lend upon interest; that the LORD thy God
> may bless thee in all that thou puttest thy hand unto, in the land whither
> thou goest in to possess it.

As far as Christianity goes... the New Testament doesn't say anything about charging interest on loans. Attitudes have gone back and forth over the centuries.

The Koran, however, does completely forbid charging interest.

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