HDTenEightyP/NetNews huggingface dataset:
From: tayloe@uinpla.npl.uiuc.edu (Rex Tayloe)
Subject: Re: Desperate situation
Reply-To: tayloe@uinpla.npl.uiuc.edu (Rex Tayloe)
Organization: Nuclear Physics Laboratory, University of Illinois, Urbana-Champaign
Date: Tue, 26 Jan 1993 20:02:31 GMT

In article <1993Jan26.183234.20186@mksol.dseg.ti.com>, blanton@mksol.dseg.ti.com (John F Blanton) writes:
>THIS IS A HOMEWORK PROBLEM
>
>The game of Russian roulette consists of the following steps:
>
>a.  Load a 6-shot revolver with 1 bullet and 5 empty chambers.
>b.  Spin the cylinder.
>c.  Point the gun at your head and pull the trigger.
>
>On the average, how many times can one person play this game
>(steps a, b, c)?
>
>This assignment is due at 5 PM today.  Our class started out with
>a mix of theorists and experimentalists.  Now all of the     
>experimentalists are dead, and the theorists are confused.
>
>We need help.
>
>(solution tomorrow)
>
>John Blanton
>blanton@lobby.ti.com

    Look up the "negative binomial distribution".  The answer is 6.


    -        Rex Tayloe              TAYLOE@uinpla.npl.uiuc.edu       -
    -        U of Illinois           TAYLOE@uiucnpl.bitnet            -
From: mtitus@umsa.umd.edu (Marvin A. Titus)
Newsgroups: sci.math.stat
Subject: PC version of BMDP
Date: 26 Jan 93 16:06:49 GMT
Distribution: usa
Organization: University of Maryland System Administration

I am making this inquiry for a friend. Does anyone know if there is a PC
version of BMDP? I would really appreciate any responses to this
question!

Thanks.
From: yan-dicky@cs.yale.edu (Dicky Yan)
Newsgroups: sci.math.stat
Subject: Re: Desperate situation
Date: 26 Jan 1993 23:12:54 -0500
Organization: Yale University Computer Science Dept., New Haven, CT 06520-2158
NNTP-Posting-Host: salmon.zoo2.cs.yale.edu

In article <00967347.5659DB00@uinpla.npl.uiuc.edu> tayloe@uinpla.npl.uiuc.edu (Rex Tayloe) writes:
>In article <2581@blue.cis.pitt.edu>, wbdst+@pitt.edu (William B Dwinnell) writes:
>>
>>Rex: How are you defining the "average"? Do you mean the mean number of tries
>>successfully past by all people trying this? Do you mean the number of
>>tries at which half the people are dead? Possibly you mean something
>>else altogether?
>
>   The problem was to determine the average number of times you pull the
>trigger before you get shot. = sum of number of triggers pulled in game
>i/number of games. This process would be described by the negative binomial
>distribution (or, more specifically, the geometric distribution). This
>distribution describes the probability for obtaining the kth success in the rth
>trial. In this case k=1 (the geometric distribution). The n.b.dist is given by:
>           
>                   P(r;p) = p(1-p)**r-1    (for k=1)
>     where p = probability of success in each trial (= 1/6 in this example)
>
>     This distribution has a most probable value of 1 and an mean value of 
> 1/p = 6.  So by "average" I mean "mean".  = (
>                                             /rP(r;1/6)dr 
>                                             )
>6 does seem high doesn't it?  I think that it is because of the long tail on 
>this distribution.  It also just occurs to me that a most probable of 1 seems 
>strange also. Oh well, I hope somebody yells if this is wrong. 
>
>
>    -        Rex Tayloe              TAYLOE@uinpla.npl.uiuc.edu       -
>    -        U of Illinois           TAYLOE@uiucnpl.bitnet            -
>
Yeah, it's the Geometric Distribution. The word "average" can be explained
in the following sense. You ask 1000 volunteers for the game. Ask each
of them to repeat steps a-c until he/she kills himself/herself. 
Then you yourself (the sole survivor of the game) records the data.
e.g. Mary kills herself after repeating steps a-c  4 times
     John kills himself after repeating steps a-c  6 times
          :       :      :       :         :          :

       ... etc.

The average is the mean of these numbers. Suppose your sample only includes
Mary and John, the (sample) average will be 5. For this particular problem the
answer is 6 (this is the mean for the distrubution, not for the sample). 
It means a person who plays the game is expected to die after
repeating steps a-c 6 times. (If you find the mentioning of sample and 
distribution mean confusing, just forget about this paragraph, okay?)

Dicky Yan.
Newsgroups: sci.math.stat
From: steve@alder.lle.rochester.edu (Steve Swales)
Subject: Recommendation for statistics package, please
Reply-To: steve@lle.rochester.edu (Steve Swales)
Organization: UofR Laboratory for Laser Energetics
Date: Fri, 22 Jan 93 00:30:46 GMT

Greetings. I've been watching for an FAQ list in this group, but
haven't seen one.  I apologize for this obvious FAQ, but, can someone
please recommend general purpose interactive statistical package(s) to
run on workstation (e.g. Sun SPARC) and possibly other non-PC
computers (e.g. VAX/VMS), and where to obtain them? We are in need of
phasing out RS1 on our VAX, because it is too expensive for the
limited use which is made of it.  I'm trying to talk with BBN
Software, Inc. about their workstation version of RS1, and waiting for
information from them on this and their new product (all I know so far
is that they have SOMETHING new), but I believe there must be far
newer and surely better products out there.  The other package I know
exists is SAS, but have no other information about it. I would very
much appreciate knowing where to call/write to get more information
about SAS and any other packages which people recommend (or recommend
AGAINST).  Valuable features would be:
	1) Interactive and programmable.
	2) Full complement of statistical analysis capabilites (obvious?).
	3) Good plotting capability (PostScript & X, at least).
	4) Access to external SQL databases (Ingres).
	5) Ability to 'import' existing RS1 data and procedures would
		be great, but probably not a realistic expectation.

 Please reply by e-mail if possible.  I will summarize to this group
(sci.math.stat) if there is interest.

Thanks,

-steve

--
 +---------+--------------------------------------------------------+---------+
 |         | Steve Swales                      (716) 275-7730,-5101 |         |
 |         | steve@aldur.lle.rochester.edu         (128.151.32.171) |         |
 |         | University of Rochester            250 East River Road |         |
 |         | Laboratory for Laser Energetics    Rochester, NY 14623 |         |
 +---------+--------------------------------------------------------+---------+
From: wbdst+@pitt.edu (William B Dwinnell)
Newsgroups: sci.math.stat
Subject: Re: PC version of BMDP
Date: 26 Jan 93 19:23:07 GMT
Distribution: usa
Organization: University of Pittsburgh


Yes, there is BMDP PC-90 (maybe there's an even later release, I don't
know). 
Newsgroups: sci.math.stat
From: ueberla@cs.sfu.ca (Joerg Ueberla)
Subject: classification trees needed
Keywords: calssification trees
Organization: CSS, Simon Fraser University, Burnaby, B.C., Canada
Date: Tue, 26 Jan 1993 10:03:16 GMT

Hello,

   I need to use classification and regression trees (as for example
   published in Breiman et. al). Can anyone point me to some software
   package that provides this (preferably shareware)? your help would
   really be appreciated.
   Thanks,

Joerg
(ueberla@cs.sfu.ca)

Newsgroups: sci.math.stat
From: an1060@anon.penet.fi
Subject: Lotteries???
Organization: Anonymous contact service
X-Anonymously-To: sci.math.stat
Date: Thu, 28 Jan 1993 18:13:40 GMT

X-Anon-To: sci.math.stat


Hello,

I am curious to know some "strategies" for increasing one's expected
winnings in a state lottery.

Just for conversation sake let me explain the New York State Lotto 54.
One chooses any 6 numbers from 1 through 54 (inclusive).  The State
randomly selects there 6 (plus a supplemental number, but we need not
discuss this) by placing ping pong balls, numbered 1 - 54, in a hopper,
then the balls are "spit" out one at a time...etc...  The prizes are 
determined by how many numbers a player matches.  All 6 win 1'st, any 5
of 6 win 2nd, 4 of 6 for 3rd, and 3 of 6 plus the supplemental win 4th.

Anyhow, basic probability theory suggest to me that any one of the
C(54,6), i.e. 25827165, different combinations is equally likely to
win 1st prize.  However, I have read/heard of people who have some
kind of system that yields a greater pay-off than just random selection.
In fact, I recall reading about a math professor, from Florida I believe,
who as a demonstration to his class won many times (perhaps not the 1st 
prize, but 2nd or 3rd repeatedly)!!!  Does anyone know about this??
Who is this person??  What is his strategy??   Or any strategy, supported
by probability/statistics theory, that yields better than average payoffs??

I would like to present such a mathematical treatment to my class.
Thus far, I only discuss the combinatorics of the system, and keep
telling my classes that all selections are equally likely...but feel
I am not telling them the whole story!!

Many thanks in advance!!!

Abe Mantell

mantell@ams.sunysb.edu


-------------------------------------------------------------------------
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Due to the double-blind system, any replies to this message will be anonymized,
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From: wbdst+@pitt.edu (William B Dwinnell)
Newsgroups: sci.math.stat
Subject: Re: Desperate situation
Date: 26 Jan 93 19:43:43 GMT
Organization: University of Pittsburgh


Assuming that you mean by the "average" person, the point at which half
of the people have diesxxx (sorry, I did it again!) diesxsasdc
died, the following progression applies:
Turn number    Cumulative proportion of people dead
1                .1667
2                .3056
3                 .4213
4                .5177  <-- Oops! Half of 'em are dead! Yuck!
  There may be a way to get an exact figure, like 3.9something something,
but it escapes me at the moment...
Any more questions?
By the way a Monte Carlo simulation, or a Las Vegas simulation might
help here...
From: wbdst+@pitt.edu (William B Dwinnell)
Newsgroups: sci.math.stat
Subject: Re: Desperate situation
Date: 27 Jan 93 14:05:06 GMT
Organization: University of Pittsburgh


While I'll readily accept the definition (interpretation) of "average",
as you guys are using it, with respect to this problem, it should
be noted that means are not just "means". By this I mean that a mean
is just taking over a series of numbers, but rather it s
is of a series of numbers, over some domain. Remember, when you
calulate them mean, you e perform a summation, and divide by some value
(typically the highest value in the domain).  So, you have calculated
the mean number of attempts, over people who try, whereas I 
calculated the number of tries, when half of the people would be 
dead (the median). Actually, my number is a mean, but  in a different
domain. My number was the mean un  number of attempts made, over 
possible outcomes (I think).
From: jerry@hnrc.tufts.edu (Jerry Dallal)
Newsgroups: sci.math.stat
Subject: Re: Desperate situation
Date: 27 Jan 93 01:45:32 GMT
Organization: USDA HNRC at Tufts University

In article <1993Jan26.183234.20186@mksol.dseg.ti.com>, blanton@mksol.dseg.ti.com (John F Blanton) writes:
> THIS IS A HOMEWORK PROBLEM
> 
> The game of Russian roulette consists of the following steps:
> 
> a.  Load a 6-shot revolver with 1 bullet and 5 empty chambers.
> b.  Spin the cylinder.
> c.  Point the gun at your head and pull the trigger.
> 
> On the average, how many times can one person play this game
> (steps a, b, c)?
> 

An interesting (mathematically) variant is a,b,c,c,c, . . .
From: wbdst+@pitt.edu (William B Dwinnell)
Newsgroups: sci.math.stat
Subject: Re: pseudo random numbers
Date: 21 Jan 93 22:34:04 GMT
Distribution: usa
Organization: University of Pittsburgh


Probably the book I recommend the most: "Numerical Recipes in Pascal"
(or "in C", or "in Fortran"), by Press, Flannery, Teukolsky, and
Vetterling, published by Cambridge University Press. It runs a little
over $40 (give or take), and is well worth every penny- no lab should
be without one! Oh yeah, try to get the new 2nd edition (which I have
only seen for C and Fortran- no Pascal this time, darn!), it has
even more stuff in it.
From: siohan@levy.loria.fr (Olivier Siohan)
Newsgroups: sci.math.stat
Subject: Conjugate prior density of Gamma distribution
Date: 21 Jan 93 13:19:23 GMT
Organization: Crin-Inria-Lorraine


     Hello,



I would like to know what are the conjugate prior densities of a Gamma
distribution.
In other words, if $a$ and $l$ are the parameters of the
following Gamma density:
\[
\gamma(a,l,x) = a^l / \Gamma(l) \times x^{l-1} \times \exp(-a.x)
\]
what are the prior densities of:
	a (l is known and fixed),
	l (a is known and fixed),
	(a,l) (joint conjugate prior density)?


Please answer by e-mail. Thanks in advance,

Olivier

-- 
+---------------------------------------------------------------+
! Olivier SIOHAN                ! Phone : (33) 83.59.20.95      !
! CRIN / CNRS - INRIA Lorraine  !                               !
! B.P. 239                      ! Fax : (33) 83.41.30.79        !
! 54506 Vandoeuvre-Les-Nancy    !                               !
! France                        ! E-mail : siohan@loria.fr 	!
+---------------------------------------------------------------+
From: hirai@aster.osaka.jip.co.jp (Hirai Kazuto)
Newsgroups: sci.math.stat
Subject: Decision Making References
Date: 20 Jan 93 07:37:55 GMT
Distribution: sci
Organization: /home/hirai/.organization



-- Hi,networkers --

 Please teach me some famous and standard references(if possible, 
written in English) which are classfied into following topic( or theme ) ;
   "Decision Making"
    ---fields: statistics,general social system, marketting reaserch,etc.

 I hope anyone could send me emails about those articles.


 thanks in advance


       
              $B"!(J        +++++++++++++++++++++++++++++++++++++++++++++++++++++++++                 
    JAPAN     $B"#(J          Kazuto Hirai (field:Environmental Science &
              $B"#(J                              Quantitative Analysis )
        $B"#"""#"#(J          mail address: hirai@aster.osaka.jip.co.jp
       $B"!(J $B"!(J              Department of Social System, Osaka Office, 
                          Japan Information Processing Service
                          Co.Ltd.,            Osaka 550, Japan  
 $B""(J:Osaka(Kansai area) 
                        +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Newsgroups: sci.math.stat
From: tayloe@uinpla.npl.uiuc.edu (Rex Tayloe)
Subject: Re: Desperate situation
Reply-To: tayloe@uinpla.npl.uiuc.edu (Rex Tayloe)
Organization: Nuclear Physics Laboratory, University of Illinois, Urbana-Champaign
Date: Wed, 27 Jan 1993 02:14:33 GMT

In article <2581@blue.cis.pitt.edu>, wbdst+@pitt.edu (William B Dwinnell) writes:
>
>Rex: How are you defining the "average"? Do you mean the mean number of tries
>successfully past by all people trying this? Do you mean the number of
>tries at which half the people are dead? Possibly you mean something
>else altogether?

   The problem was to determine the average number of times you pull the
trigger before you get shot. = sum of number of triggers pulled in game
i/number of games. This process would be described by the negative binomial
distribution (or, more specifically, the geometric distribution). This
distribution describes the probability for obtaining the kth success in the rth
trial. In this case k=1 (the geometric distribution). The n.b.dist is given by:
           
                   P(r;p) = p(1-p)**r-1    (for k=1)
     where p = probability of success in each trial (= 1/6 in this example)

     This distribution has a most probable value of 1 and an mean value of 
 1/p = 6.  So by "average" I mean "mean".  = (
                                             /rP(r;1/6)dr 
                                             )
6 does seem high doesn't it?  I think that it is because of the long tail on 
this distribution.  It also just occurs to me that a most probable of 1 seems 
strange also. Oh well, I hope somebody yells if this is wrong. 


    -        Rex Tayloe              TAYLOE@uinpla.npl.uiuc.edu       -
    -        U of Illinois           TAYLOE@uiucnpl.bitnet            -

Xref: sparky sci.math.stat:2852 comp.sys.sun.apps:3078
Newsgroups: sci.math.stat,comp.sys.sun.apps
Subject: Splus:  fortran subroutines
From: mwalker@ehd.hwc.ca (Michael Walker)
Date: 21 Jan 93 09:29:37 
Distribution: na
Organization: Health and Welfare, Canada
Keywords: Splus,dyn.load,f77 


Here is a brief description of my problem and what I have done so far to try
to solve it:


     I have a fortran subroutine that I want to "dyn.load" into Splus
(Version 3.0 for SUN4).  Because I am only learning how to load subroutines,
this subroutine merely tells you if a string begins with "h" or not.

     The subroutine, little.f, was compiled using f77 and the command

% f77 -o -Bstatic little.f

     I first tried to load the object file into Splus using dyn.load():

> dyn.load("little.o")
Error in dyn.load("little.o"): No definition for symbol "_s_cmp"
Dumped

     Apparently dyn.load() doesn't have access to the fortran library that
tells it how to compare two strings.  I then tried using dyn.load2():

> dyn.load2("little.o")
ld: : bad magic number
ld: No such file or directory
Error in dyn.load2("little.o"): 'ld -A ...' failed
Dumped


     I know the following:

1)  dyn.load() does not work if any "system libraries" need to be "included".
I am no computer expert and so I'm not sure I know what this means.

2)  The file LIB_HINT is where it should be, and it looks *exactly* the same
as those on systems where dyn.load2() works properly.

     I am guessing that this is a local problem, having something to do with
the way Splus was installed here.  Unfortunately, nobody here can seem to help
me.  If anyone else has had this problem or can see where solution lies,
please reply by E-mail.

     Thanks in advance for any suggestions.
     MJ
Newsgroups: sci.math.stat
From: andersh@maths.lth.se (Anders Holtsberg)
Subject: Re: Desperate situation
Organization: Lund Institute of Technology, Sweden
Date: Wed, 27 Jan 1993 09:10:18 GMT

There is a very simple solution:

X  number of shots
Y  event that first shot causes death

now

E(X) = E(X given Y)P(Y)+E(X given not Y)P(not Y)

and

E(X) = m
E(X given Y) = 1 of course
E(X given not Y) = m+1  this was the trick!

fill in the details yourself.

Anders H
Newsgroups: sci.math.stat
From: blanton@mksol.dseg.ti.com (John F Blanton)
Subject: Re: Desperate situation
Organization: Texas Instruments, Inc
Date: Wed, 27 Jan 1993 15:15:37 GMT

As promised, here is the solution:

The probability of surviving one round (interesting choice of
words there) is 5/6.  The probability of surviving N rounds
is           N
    p = (5/6)

The probability of surviving N-1 rounds and being killed on the
Nth round is
                N-1
   p = 1/6 (5/6)


The average lifespan of someone who plays Russian roulette is

                      N           i
   L = lim            Sum [i (5/6) ]/6
       N-->Infinity   i=1

                               N
     = lim            1 - (5/6)
       N-->Infinity (------------) / 6
                               2
                      (1 - 5/6)

     = 6.

My thanks to all who submitted solutions.  As you can see, I have
left out some steps, and the last limit expression presumes that
the limit of a derivative is the same as the derivative of the
limit.  I didn't verify that this is always true, but it turned
out to be true in this case, so I didn't type in the more complicated
limit expression that would have resulted by taking the derivative
first, then computing the limit of the result.

John Blanton
blanton@lobby.ti.com
Newsgroups: sci.math.stat
From: ph@physiology.oxford.ac.uk (Patrick Haggard)
Newsgroups: sci.math.stat
Subject: Fit a circle to (x,y) datapoints?
Date: 26 Jan 93 14:14:16 GMT
Organization: Physiology Department, Oxford University, Oxford, UK.
Originator: ph@galen.physiol


I have 40 (x,y) datapoints which I hypothesise form the arc of a 
circle of unknown origin and radius.  I want to find an estimate
of the radius of the circle.  The preferred platform is SAS:
I imagine proc nlin; would do it, but what is the neatest way
to specify y in terms of x.  Any suggestions on how to tackle this.
Thanks

Patrick Haggard
Newsgroups: sci.math.stat
From: Roger De Abreu <roger@glenn.uwaterloo.ca>
Subject: Systat for Win 3.1 Anyonbe ??
X-Xxmessage-Id: <A789CEF49201361D@eolite.uwaterloo.ca>
X-Xxdate: Mon, 25 Jan 93 17:08:04 GMT
Organization: Earth Observations Lab
X-Useragent: Nuntius v1.1.1d11
Date: Mon, 25 Jan 1993 22:04:47 GMT

Has anyone used Systat for Windows yet?  I am curious how different it is
from the DOS version in utility and functionality ??  

Thanx in advance...rogman
From: winzar@newsman (Hume Winzar)
Newsgroups: sci.math.stat
Subject: Re: Data on AIDS in USA
Date: 26 Jan 1993 18:05:09 GMT
Organization: Commerce, Murdoch University
NNTP-Posting-Host: 134.115.160.7

In article <1993Jan25.163828@masg1.epfl.ch> michaud@masg1.epfl.ch (Pierre-Alain Michaud) writes:

>o  Is there some public data base on AIDS, and if so, how to connect?

>o  Particularly, I am interested in the number of diagnosted cases per
>   6 months in the United States. The data should be as actual as
>   possible.

Try the SCI.MED.AIDS  newsgroup

  - - - - - - - - -
 |      _--_|\     |   Hume Winzar
 |     /      \    |   Commerce School,
 |     *_.--._/    |   Murdoch University,
 |           v     |   Perth, Western Australia
  - - - - - - - - -  
                       E_Mail winzar@csuvax1.csu.murdoch.edu.au
                       Phone: (09) 310 7389
                       Fax:   (09) 310 5004
Newsgroups: sci.math.stat
From: R0264@vmcms.csuohio.edu
Subject: Re: Measures of Multi-Modality
Organization: CSU
Date: Fri, 22 Jan 1993 18:59:25 GMT

In article <1jkb22INN8ob@pith.uoregon.edu>
joe@decoy.uoregon.edu (Joe St Sauver) writes:
 
>
>I've got a researcher who is looking for a measure of
>multi-modality (or "bi-polarity," if you will) such
>that unimodal data would have a small score, and bimodal
>or trimodal or n-modal data would have a large score.
>
>I'm at a loss for what to recommend -- any suggestions?
>
>Thanks,
>
>Joe St Sauver (joe@oregon.uoregon.edu)
The sample measure of kurtosis would be one approach, but might not be
sufficient.  It is 4th central moment divided by square of 2nd, if I
remember correctly, and has value 3 for normal, and smaller values for
platykurtic distributions.
Organization: University of Illinois at Chicago
Date: Thu, 28 Jan 1993 05:41:14 CST
From: LARRY GRIMM <U19163@uicvm.uic.edu>
Newsgroups: sci.math.stat
Subject: History of Multivariate

Does anyone have a good reference for the history of multivariate
data analyses?  Also, I could use a reference for an overview of
the various types of analyses.  Not how to conduct the analyses, rather
an overview that categorizes the numerous mulitvariate techiques.
thanks.
Newsgroups: sci.math.stat,osu.statistics,bit.listserv.spxsx-l,bit.listserv.stat-l