From: sommar@enea.se (Erland Sommarskog)
Newsgroups: rec.music.misc,alt.rock-n-roll
Subject: UAP #23 - Neil Young, reminder
Keywords: Usenet Artists Polls
Date: 11 Oct 92 22:03:57 GMT
Followup-To: poster
Organization: Enea Data AB

So, as promised a vote on Neil Young's production. I like to thank
Wayne Francis (pgwfranc@atlas.cs.upei.ca) who provided me with a
discography without which this vote would have been possible.

The discography appears below and you are encourage to use it as
a template for you ballot. I've decided to include the Buffalo
Springfield and the CSN&Y albums. Some people may disagree with
that, and they may be right. Personally I'm not very well acquainted
with Mr. Young, so I cannot say what makes sense or not.

Deadline for this poll is October 17th.

If you are new to these polls, please read the instructions following
the template before you vote. If you interested in reading about the
algorithm I use to compute the results, there is a descpription following
the instructions.

This should be a complete list of Neil Young's albums, including
albums with Buffalo Sprinfield and Crosby, Still, Nash & Young.
Feel free to add missing items, but please respect that bootlegs
and interview albums are not included.

&BEGIN
Buffalo Springfield
Buffalo Springfield Again
Last Time Around
Neil Young
Everybody Knows This Is Nowhere
Deja Vu
After The Goldrush
Four Way Street
Harvest
Journey Through The Past
Time Fades Away
On The Beach
Tonight's The Night
Zuma
Long May You Run
American Stars'N'Bars
Decade
Comes A Time
Rust Never Sleeps
Live Rust
Hawks And Doves
Reactor
Trans
Everybody's Rockin'
Old Ways
Landing On Water
Life
This Note's For You
American Dream
Freedom
Ragged Glory
Weld
Arc Weld
&END

How to vote
-----------

Use the list above as a template for your ballot. Sort the list
so that your favourite comes right after the &BEGIN and your
least favourite just before the &END. Delete albums you are not
familliar with. One album by line. No numbering. Please delete
quote characters like ">" from your ballot.

If you can't tell two or more albums apart you can declare a
tie. You do this by preceding the albums with &TIE. The tie
lasts until the next &END. The number of &END on the ballot
must be equal to the number of &TIE + one for the &BEGIN.

If you feel that there is a big gap between two albums you
can mark this with a filler. A filler has the format &FILLERn
where n is a positive number, default is 1. Notice that a very
big value of n make little sense; the net effect is the same
declaring an &TIE on the albums separated by the &FILLER.

To participate you need to know at least two albums, so you don't
have to be shy. Ballots are weighted, so the more you albums you
know, the more influence do your ballot get.

For further details on the algoritm, see below if you are interested.

*MAIL* your vote ballot to me, sommar@enea.se. I try to acknowledge
all votes, so if you do not receive an ack after a few days, please
mail me again.

If your mailer leave a decent return address *and* your ballot mail
has a non-empty subject line, you will get the results in your mailbox.
If you want the results to another address, please state so, but no
guarantees.

You are welcome to send in a vote for a friend who does not have net
access. Just indicate that the vote is for someone else so I know that 
it's not a duplicate.

Have fun!

The Algorithm
-------------

This an example ballot for an imagninary group: (The numbers in the
right are NOT part of the ballot as you write it, but are used for
the description below.)

&BEGIN
She Comes in the Morning                      0.5
Next Day                                      0.4
&TIE
Looks Like Trouble                            0.25
Futuralized                                   0.25
&END
On the Way Down                               0.1
Cram it!                                      0.0
&FILLER4
Last Really Crappy Album                     -0.500
&END

The algorithm to compile the results of a polls consists of a
number of steps.

Step 1:
For each individual ballot, the intervall from -0.5 to 0.5 is sliced
up at (N + F + 1) equidistant points, where N = number of entries,
and F = number of fillers. In the example ballot N = 6 and F = 4.
The top album gets 0.5 points, next album ((N+F) / (N+F+1)) - 0.5
points, third best gets ((N+F-1) / (N+F+1)) - 0.5 points etc, down 
the last which gets -0.5 points. If two or more albums are tied,
they get the average of the involved points. The net result for
the example ballot is illustrated by the number on the right side.
(Side note: if we forget the fillers, the method corresponds to the 
one you use for pairs competitions in bridge.)

Step 2:
In order to avoid distortion from voters who only know the 2-3
most popular albums, the ballot is weighed so that the points 
from step 1 are multiplied with sqrt(N).

Step 3:
All ballots are added together and for each album we get a number
of points P = ((p1 + p2 ... pM) * 1000 / M) * C + 500, where M = 
the number of ballots the album appears on, and C is a poll constant.
Thus, the result for an album is indepentent on how well-known it is,
However there is a cut-off rule, so albums which only appears on one
or two ballots are excluded from the final result.

The Poll Constant:
This constant is sqrt(B/T) where B where B is the number of ballots 
in the poll and T is the total number of entries on these ballots.
The idea with the poll constant is to remove the effect of the weighing
factor from the range of the points, so we can compare polls with
each other. If an album tops all ballots, it will get 1000 and 0 if
it is ranked last by all voters. Note however that this compensation
is a rough model. If an album tops five ballots of ten, and is not
mentioned on the other five, its result can be bother higher and 
lower than 1000 depending on the weight of these ballots.
-- 
Erland Sommarskog - ENEA Data, Stockholm - sommar@enea.se
There are many sorts of Macedonians: Greek, Bulgarian, Roumanian, Macedonian...
Newsgroups: rec.music.misc