Some thing is wrong with Canadian coin valuation and needs to be investigated. I found this on both large cents and silver 5c, but it probably a deeper systematic problem. The examples I use are all slabbed unc coins on ebay so grading is not an issue. The 3 coins I list compares ebay price with numista valuation.
1913 5c unc 272 vs 170 on ebay
1914 5c unc 532 vs 70 on ebay
1917 5c unc 485 vs 80-110 on ebay
Please provide ebay listings to check/compare. This one or this one would tend to support Numista value displayed.
If you click on the link "See more past sales" at the bottom of the 5 cents page you can see various auction sales and values tend to make sense for the 1913 for instance.
Amounts also sometimes include fees while price on ebay do not necessarily so there might be some difference there.
Of course, some exceptions exist like for the 1913 here.
Sapientiae plerumque stultitia est comes.
Si c'est un grand plaisir d'être reconnu par ses amis, c'est peut-être encore plus flatteur d'être reconnu par ses adversaires.
Be yourself; everyone else is already taken.
UNC in the Numista listings include everything from MS60 to MS70 coins. Obviously the very high grades will drive the "average" price way up. Unless you know the breakdown of grades vs. price, the values for UNC in Numista don't mean much.
As far as grades above ms64 it is my opinion they should not be included in numista valuations. I deal in US coins in MS65 to 70 all the time. Here is an example of 1937 walking liberty half dollar, a popular series
of US collectors. High grade examples of walkers above ms65 are fairly scarce due to the great depression and the inadequate equipment at the mint required to strike these coins fully. Here is gray sheet pricing:
MS 66 and 67 probably represent only3-5% of the population of this date, but if one of the higher grades gets used in the calculation, it completely skews the numista valuation.
I plotted the auction prices listed on the coin page for KM #22 vs. grade (deleting the 2 abnormally high ones). The 2 you reported above are red. As you can see the very high grades drives the average price up considerably, with the average price consistent with what Numista shows for "UNC."
Your comment about the higher grades skewing the Numista values is obviously correct. You could exclude published auction prices of coins MS65 and above but how would you do that for member entered coins where the grade is not available?
About excluding specific grades, that might be "consistent" for this specific coin but for some coins MS64 and over are not that scarce.
One shall also keep in mind that Numista values do not include a time dimension i.e. price evolution with time.
Values are more an illustration of trends than a perfect representation of the "market"; that's also one reason for which the sales entries are kept at the bottom of the page. Members can check the values with listings that are dated, have explicit grading, etc.
Sapientiae plerumque stultitia est comes.
Si c'est un grand plaisir d'être reconnu par ses amis, c'est peut-être encore plus flatteur d'être reconnu par ses adversaires.
Be yourself; everyone else is already taken.
Overall I love the numista pricing: in fact I use it for selling my coins.As I see it pricing does not work for unc coins from popular countries such a United Kingdom, US or Canada when you are grouping 11 different grades in one "unc" column. I perfectly understand why you can not have pricing for these different grades.
However, if you use reverse logic and combined the 6 grades of gd thru au for the above counties and took a median posted to a single column, it would be an equivalent statistical anomaly to what you now have in the unc column.
As I posted previously, I believe a better solution would be to eliminate any coin MS65 or above from the calculation to eliminate the outriders.
The higher grades are actually already excluded by the algorithm if they represent a small percentage of the number of sales. The prices on Numista are more or less median values, not averages. So all the outsider values are de facto excluded. For this reason, excluding grades MS65 and above would have a quite small impact.
It would anyway be impossible to do in the current situation, since values are computed not only from the past auctions, but also from the Numista users who indicate how much they paid for the coin, and we have no field yet to enter the exact grade.
More generally, I agree that more thorough price research is needed for UNC, especially for US and Canadian coins, since prices vary a lot depending on the exact grade.
One more remark regarding pejounet's comment: Numista takes into account the date when the coin was bought. Older sales and collections have less weight in the computation of the value than the more recent ones.
Status changed to Rejected(Xavier, 17 May 2022, 09:52)
