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Old 05-11-2018, 05:29 PM
zenstat zenstat is offline
Vintage Drum Guru
 
Join Date: May 2010
Location: Auckland, New Zealand
Posts: 1,558
Default Re: Is this a 1930s custom made A Zildjian?

How I collect data is a different question from how I present it in charts. The chart is a summary which uses statistical techniques to display the data but not get to bogged down in detail. If you have a look at this description of how to read the box plots:

http://black.net.nz/avedis/avedis-prices.html#Boxplots

you will see that the actual distribution goes down to the bottom of the whisker. That bottom whisker goes down to 1650g.

Today I've got 127 cymbals with 1960s trademark stamps on them in my database. There might be more later today because I'm about to do some more entry. Of these 127, 20 did not have a weight given. Of the 107 left the lightest 5 are:

1650g (25-Feb-2016, asking $290 (EUR280+ship) not sold on eBay)
1695g (THIN CRASH ink)
1708g
1718g
1790g (larger bell so presumed Crash or Crash Ride model)

and so on at that level of detail to an Earth Ride at 3368g. That first one is 99% likely yours. I've also got a link to a for sale thread on another site which included an iPhone sound file and photos, from an Italian based seller with a different screen name.

I don't claim that my data collection is perfect and I've got 100% coverage, but its pretty good. Because your cymbal was marked as did not sell on eBay the price there does not enter into my price analysis. Now that I know it sold for $250 I can amend the record to show that as well.

Doing this sort of research is best likened to an iceberg floating on the water. About 10% of the work appears above the surface of the water. But 90% is invisible below. That includes a huge amount of data collection, data cleaning and deduplication, "sanity checks" using previous data models to vet new observations which are outliers, statistical analysis and modelling of the results with new data added, selection of what results to show, and finally posting information for free public use which has been thoroughly vetted.

I mentioned model ink before and as you can imagine that is another apparently simple summary which requires a lot of data collection to find examples from different production eras with still have model ink intact, and where a plausible weight is given. It isn't just looking for a needle in a haystack. It is looking for a particular piece of hay in a haystack when all the pieces of hay look very similar and have to be examined one at a time.

A specific example of data cleaning is corrections to incorrect identifications by sellers which means examining every photo in detail. Having kept track of the discrepancies those form another analysis

http://black.net.nz/avedis/avedis-pr...nfusion-matrix

which shows that 25% of Avedis Zildjian cymbals for sale are either unidentified by the seller, or misidentified as to production era.
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For every expert, there is an equal and opposite expert, but for every fact there is not necessarily an equal and opposite fact (Thomas Sowell, 1995 in The Vision of the Anointed)

Paiste 602/Sound Creation research click here
Which K Stamp? A DIY tool click here
Old K prices and weights click here
Avedis Zildjian gallery and timeline click here
Old A prices and weights click here
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