Before we begin, let me say that personally, I have short stories for sale at 99c, compilations for $1.99, and plan novels for $2.99, $3.99, and $4.99 price points.
Really, perfectly honestly, I understand frustration that a lot of authors have with the "race to the bottom" mentality, but the reality of the situation is that ebooks have a great drawback: you can neither lend nor borrow the great majority of them. And it's kind of difficult to do even if you can.
I remember reading a statistic many years ago that the average mass market paperback book was read 6 times before it went to the dump. (This stat was before recycling was common.) Hardbacks had more reads before dumping.
Ten years ago, I purchased a fraction of dead tree books that I read. My friends and I, when at each others' houses, perused each other's stacks and took home books. There was usually a perfunctory, "You mind if I borrow these?" involved.
Sometimes the books were returned.
Usually, they were passed on.
That number, "6", is interesting.
Many mass market paper backs (mmpbs) are priced around $5.99. $6/6 reads = $1 per read.
The most acceptable price for a non-lendable ebook for a lot of people is 99c.
I think that books that are available as mmpbs should be 99c, and I plan to price that way.
Trade paperbacks, usually priced around $12-15, should be $12/6 reads = $2, or $1.99.
New issues, like hardbacks, should be $23.99/6 reads = $4, or $3.99.
Really excellent, large novels should be $29.99/6 reads = $5, or $4.99.
I think people are subconsciously doing that math, and I think that's why the price points have settled out at those numbers.
For short stories, the math is fuzzier, but possible to discuss.
In The New Yorker, there are usually about 20 pieces, plus or minus a few, and counting "Goings On About Town" as 1 piece, etc. If you have a subscription, that's about $1.50 per issue ($70/47 issues per year = 1.489). So that equals that I pay about 7.5 cents (= $.075) per short story that I read in The New Yorker. And I usually pass my NYer on to one other person.
On the other hand, The New Yorker usually pays a new writer around $10,000 to publish a short story, 1st NA serial rights, plus some other electronic rights. On their advertising page, they say that their average print audience is 3.9 million people. So a writer gets 0.26 cents per print audience member, (that's not a quarter per person, that's zero point twenty-six 100ths of a penny, or 26/100 of a cent, or about 1 penny per 4 reads.)
So that's even less.
Short stories should, really, be 10c, or 25c, or 49c, at most. I wish Amazon, Smashwords, and the other outlets would let us do that.
Anyway, that's my 2 cents,