What is stock valuation?

When a firm is listed in a stockmarket, it has a market price.
So everybody knows what it is worth.
Thus why the need to do a valuation, if we know the price?
The trick is that if you buy the stock, it is that you think
it can reach an higher price. If you sell it it is that, it is
because either you need the money to buy a new toaster,
or you think it can reach a lower price.
Which means that valuing a stock is to estimate its
potential prices.
Mind you, I didn't say its "fair price", a theoretical concept,
but its potential price, which is a practical one.

* One or several potential prices?
You have at least two potential prices for a given asset:
the lowest and the highest potential one..
And those betwen those two extremes of course.
Among them the so-called "fair price", that might be the
pivot of the range.
So valuing a stock, as I see it, is to determine a bracket
of potential prices.

* How to find this range ?

a) Fundamentals play a part. The first element of the
bracket would be economic scenarios about the predictable
results of the firm.
Of course there is some subjectivity in such predictions.
And some subjectivity also in the choice of the calculation
methods to infer a financial value from economic result
predictions;
Yes, valuations are always subjective to some degree.
Better admit it!

b) The second element is behavioral:
What would be the attitude and behavior of investors
towards the stock ?
What are the economic scenarios and valuations methods
the investors would choose.
What cognitive biases might interfere?
And what emotional value (image) they give to the stock,
which would add a love bonus or deduct a dislike penalty
to the valuation? Subjectiveness at power 2 !
That financial affect (market sentiment) varies also inside
a bracket, from highly bullish to highly bearish, from hatred
to adoration.

* How to combine all this?
There is a model, the only one to my knowledge, built on
the idea of assessing potential price brackets with a dual
set of calculation criteria, fundamental + behavioral.
Its main innovation is the "stock image coefficient".
You have free acces to this unique stockpricer at:
http://perso.wanadoo.fr/pgreenfinch/pricer.htm