I don't think comparing new Pis to used micro pcs is fair. Compare a _used_ Pi with a used micro pc. If you have any geek friends, it's probably not hard to find a used Pi for free.
Well, a 5-year-old chip may not count as "recent" but the RK-3588 boot chain is "almost fully open-source" [1]. And it seems like it took a major amount of effort (from Collabora, others) to get it this far. I don't know of any equivalent or newer chips that are "more" open, but would love to hear if there are.
Although that date should really only apply to the `m6502.asm` file. I think for a historical archive accuracy should be important. For example when was it licensed under the MIT license, I assume fairly recently. The file date should reflect that.
There are multiple methods of measuring multiple (related) things. What you are describing sounds more like the share of the installed base, which only works for certain types of products. (i.e. it doesn't work for consumables like apples or electricity)
I have diligently searched for this article online and have been unable to find it. (It might be on microfiche somewhere...)
I did however, find this humorous anecdote:
> A Lotus executive later joked, "The first month we shipped 62,000 copies, and the following month we got 64,000 copies back. It was such a failure they sent us the bootlegged copies back."
There are multiple ways of calculating market share (e.g. units vs dollars or for different time periods) but assuming it is measured in dollars for a quarterly time period, how would you calculate the market share based upon my sample data above?
That is how it was calculated in a published trade magazine (either Infoworld or MacWeek, I think) I'm not sure if the the analysis was done by a market research firm or the magazine.
> The only way that makes any sense is if you subtract returns for sales made in a different period to the sales period you are considering
Exactly. That's the way accounting works. They did not know in the previous quarter that the product would be returned in the following quarter, so they end up having negative sales in the current quarter.
Yes it produces "garbage output", which I find amusing.
TIL about the Herfindahl–Hirschman Index and I wanted to test it with a weird corner-case that I remember.
At one point in the late 1980's Microsoft had a GREATER than 100% market share of the Macintosh spreadsheet market.
How is this possible?
Market share (for a given period) is the participant's sales in the market divided by total sales. It just so happened that Lotus had more returns than sales of their failed spreadsheet, Lotus Jazz. So Lotus, had a negative market share and Microsoft had more sales of Excel than total sales in the market, resulting in a greater than 100% market share.
I don't remember the exact numbers and I believe there was at least one other competitor in the study. But let's just say the numbers were:
Microsoft: 102%
Lotus: -2%
In that case the Herfindahl–Hirschman Index would be 102^2 + (-2)^2 = 10404 + 4 = 10408.
So, in this pathological case it is possible for the HHI to exceed 10,000.
Edited: Added (for a given period) above, for clarity.