El Fri, 17 Apr 2015 15:31:23 -0400 Martin Blais va escriure:
>
> But then, when does your example case happen? — „stock options that have no value attached to them“. Is this because there's
> no market? Shouldn't be they valued at >0 anyway? (If there were a market, the price would be >0).
>
> It happens if you paid nothing for the options and they weren't recognized as having a cost basis. If they were essentially gifted
> to you.
They cost you $0. If they are sold for $2 next year, how much would it be the return? (e.g. the one calculated in returns.py). From 0 to 2 it's not 200%, it's more like infinite.
>
> You're confused about terminology IMO. The entire discussion can be simplified if you accept that THERE IS NO PRICE. This is a
> bridge in understanding that traders make early on in their career and that most people live their entire life without even
> considering (if you found yourself dumbfounded by the preceding statement in caps, read it again think about it some more). And I
> mean this in a very general way, there really is no "price" for anything anywhere at any time. Stop using the word PRICE, it's
> throwing you off. There are only bids and offers, and for particular quantities. This is true for stocks, for options, for the coke
> can in the machine in the office, for your electrical bill, etc. For everything.
>
I know about bid+offer, and yes it's useful to forget about the unneeded concept „price“. Trading is a good way to learn this. I agree there's no „price“, but there are similar concepts (like: midle price between offer price and bid price)
In an electricity bill they're doing an *offer* to settle it for 250 units of $, and you *bid* 250 units of $ to settle it (and they won't accept lower bids). That's commonly and unambiguously called „price“, is that right?. I don't know whether this is theoretically possible (e.g. is the offerer really getting $250 or a bit less, and is the bidder paying $250 or a bit more).
Anyway, this is already too theoretical…
> What is the cost basis of an option? It's what you paid for it (+/- adjustments later on if they even occur, but this is a detail,
> the cost basis is the amount that you paid for the position that you can deduct from the proceeds for the purpose of paying your
> taxes).
>
> What is the value of an option? Well it depends, but you can assign a value to it (a process called "marking") for the purpose of
> evaluating a portfolio of assets. That value is "the mark". If it's for your own valuation of a portfolio, you choose it. But the
> rationale for choosing is for the most part _not_ an entirely arbitrary decision. There are bases upon which you can rest to
> estimate the value of assets. It's not a sentiment.
>
I wanted to comment on this but I realized that I know very little about theories of value or about „marking“, so I don't really understand what my words mean. Some articles about „mark-to-market accounting“ seem a very interesting read if I had the time.
Thanks for introducing these topics.
I was looking for a possible glossary in beancount's documentation to check whether those definitions you sent are already written there. It would be interesting to see the beancount way to write cost basis / value / price / bid / offer / mark. But this is not really important or urgent anyway. Maybe I should do it myself to learn about it, but that will take time too.