I was looking for something, and ended up in a set of pages at
amazon.ca where most pages of stuff, were things that were "on
target". So, I waded through 20 pages of ads on items for sale.
There were a few (2?3?) main sellers or what I was looking at, and some
If one just looked at one seller, they had ads for 1 item, 2 items, 3
items, 5 items, 6 items, and so on. And the price per unit varied.
Fine. What random distribution that is readily available, occurs for
positive real numbers and has finite variance? Probably lots of them,
but lognormal is common.
my $cost = 0.15;
my $markup = 0.3;
my $z = random_normal( 1, 1, 1 );
my $n = random_poisson( 1, 2 ) + 1;
my $unit = exp( log( $cost * (1 + $markup) ) + $markup * $z );
$unit = int( ($unit + 0.005) * 100 ) / 100;
my $bundle = $n * $unit;
print "Selling $n for $bundle\n";
which as written, loops forever. In 100 trials, I had 2 bundles sell
for (slightly) less than cost, and the incoming revenue from all the
sales was almost twice the cost.
Some item pages had statements about inventory, which could be real or
not. This process can generate bundles of number and price that have
been seen before.
What it does, is make it possible to be seen by the shopping public
many more times, than if you just bundled up everything into 5's and
sold them at one price.
Not every shopper is going to look at all pages to see the totality of
ads you have. They may look enough to see that you have the same
number of the same item multiple times. Does this stop them from
shopping at your "store"? I would imagine that some of your items,
with the higher per unit costs don't see as fast as the lower priced
items, but do they all sell eventually? Or do you have to "pull
inventory" and selling them at a lower cost?
I don't know that sellers are doing this, but it sure looks close to
what my Monte Carlo model came up with.