Statistics of eBay auction of HP-15C and HP-42S

[isanchez]

Hi,

it is very interesting all your work! Maybe it is the time to update the "prices section" of the website (and many other sections...said this with absolute respect and admiration for the work done)
In my modest opinion, there are some aspects to take into account:

-Abnormal low prices are usually caused by two main reasons: -the state of the calculator (used 15c trend to be very affected and this is not welcome by collectors, which are the main (not only) addresses of old 15c), or, but this is less frequent nowadays, the owner does not know the real value of th item...this second issue has happended to me when someone offers 15c in flea markets or second hand websites (not ebay!) and does not know very well what that does worth really...it takes minutes to buy it!

-Extra high prices can occur when "new" or "with the box" is offered, and this can also affect to general conclusions.

For this reason, what do you think?, maybe the average is not the best indicator and would be better to consider a position indicator like the median or more frequent like the mode. I would suggest to consider extra-low prices like "abnormal values"...

Again, very interesting work done...congratulations. maybe could be extended to 41's!


Kind regards

Ignacio