Author:  garbanzo  Posted:  Jul 20, 2016 10:09  Subject:  Re: standard deviation on price indices  Viewed:  30 times  Topic:  Suggestions Cancel Reply

BrickLink ID Card garbanzo (322) Location:  USA, Colorado Member Since Contact Type Status Oct 3, 2013 Seller  Store: Beans_Bricks

In Suggestions, brick_projects writes:    Please implement standard deviation. By eliminating the (small number)% cheapest and (small number) % most expensively priced lots, the average price index would be "more statistically significant" in scientific terms ( less error margin ). This is only necessary for items that have at least e.g. 10 distinct lots for sale. Why this suggestion ? Yesterday i noticed one particular seller set all his prices at ( BL avg x 10000 ). This caused average price index "lots for sale" to be inflated at least tenfold. Someone else suggested he made a mistake in currency. If this one shopkeeper persists, unwanted "extreme" inflation may occur on several very common items, and those lots - for sellers not paying attention when adding to their inventory - might become impossible to sell. I don't understand the downvotes. Implementing this doesn't necessarily mean replacing current data. I voted yes, this makes sense. I would also like to see 6-month mode and median in addition to mean.

Message is in Reply To:

standard deviation on price indices - brick_projects (3656)

Please implement standard deviation. By eliminating the (small number)% cheapest and (small number) % most expensively priced lots, the average price index would [...] (96 months ago, Jul 20, 2016, to Suggestions)

Message Has 2 Replies:

Re: standard deviation on price indices - jancg (378)

Perhaps a down vote is too harsh, but several downvoters want to stress not to REPLACE the exact 'avg price' and 'avg qty price'. Leaving out the most extreme [...] (96 months ago, Jul 20, 2016, to Suggestions)

Re: standard deviation on price indices - yorbrick (1185)

[...] I voted no, as the first line of the suggestion is different to the rest. Calculating the standard deviation is fine (first line of the suggestion). The rest [...] (96 months ago, Jul 20, 2016, to Suggestions)

21 Messages in this Thread:

 Msg 1 - brick_projects (3656) 96 months ago Jul 20, 2016 to Suggestions
 Msg 2 - FigBits (3564) 96 months ago Jul 20, 2016 to Suggestions
 Msg 3 - jeslego (1050) 96 months ago Jul 20, 2016 to Suggestions
 Msg 4 - FigBits (3564) 96 months ago Jul 20, 2016 to Suggestions
 Msg 5 - yorbrick (1185) 96 months ago Jul 20, 2016 to Suggestions
 Msg 6 - FigBits (3564) 96 months ago Jul 20, 2016 to Suggestions
 Msg 7 - jeslego (1050) 96 months ago Jul 20, 2016 to Suggestions
 Msg 8 - FigBits (3564) 96 months ago Jul 20, 2016 to Suggestions
 Msg 9 - jedvii (666) 96 months ago Jul 22, 2016 to Suggestions
 Msg 10 - yorbrick (1185) 96 months ago Jul 20, 2016 to Suggestions
 Msg 11 - jancg (378) 96 months ago Jul 20, 2016 to Suggestions
 Msg 12 - ToddMyers (356) 96 months ago Jul 20, 2016 to Suggestions
 Msg 13 - jancg (378) 96 months ago Jul 20, 2016 to Suggestions
 Msg 14 - Leftoverbricks (2225) 96 months ago Jul 20, 2016 to Suggestions
 Msg 15 « - garbanzo (322) 96 months ago Jul 20, 2016 to Suggestions
 Msg 16 - jancg (378) 96 months ago Jul 20, 2016 to Suggestions
 Msg 17 - yorbrick (1185) 96 months ago Jul 20, 2016 to Suggestions
 Msg 18 - ToriHada (8887) 96 months ago Jul 20, 2016 to Suggestions
 Msg 19 - Made_In_Bricks (3994) 96 months ago Jul 20, 2016 to Suggestions
 Msg 20 - FigBits (3564) 96 months ago Jul 20, 2016 to Suggestions
 Msg 21 - wildchicken13 (876) 43 months ago Nov 17, 2020 to Suggestions