how to develop probit or multilogit models for accident data

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how to develop probit or multilogit models for accident data

ramesh
i had given the following coding
severity sv Rear end head on swipe lanewid rural drvage female alcohol
 1  1 0 1 1 7 1 21 1 1
0 1 1 1 0 7 1 20 1 1
1 1 0 1 1 7 1 27 1 1

asfinal_coded.xls

severity single vehicle rear end head on swipe rural female alcohol
fatal=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0
non  fatal=1 no=1 no=1 no=1 no=1 no=1 no=1 no=1

how to develop model for different types of collision based on severity

pl. help me
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Re: how to develop probit or multilogit models for accident data

Bruce Weaver
Administrator
"how to develop model for different types of collision based on severity"

Do you mean you want Severity (fatal vs non-fatal) to be the outcome variable for the model?

Generally, for help on how to run a logistic regression model, see the tutorial available through the SPSS Help, or look for the "textbook examples" page on the UCLA website (Google will help you find it).

Finally, note that it is more common to code yes/no indicator variables such that 1=Yes and 0=No.

HTH.


ramesh wrote
i had given the following coding
severity sv Rear end head on swipe lanewid rural drvage female alcohol
 1  1 0 1 1 7 1 21 1 1
0 1 1 1 0 7 1 20 1 1
1 1 0 1 1 7 1 27 1 1

asfinal_coded.xls

severity single vehicle rear end head on swipe rural female alcohol
fatal=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0
non  fatal=1 no=1 no=1 no=1 no=1 no=1 no=1 no=1

how to develop model for different types of collision based on severity

pl. help me
--
Bruce Weaver
bweaver@lakeheadu.ca
http://sites.google.com/a/lakeheadu.ca/bweaver/

"When all else fails, RTFM."

PLEASE NOTE THE FOLLOWING: 
1. My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above.
2. The SPSSX Discussion forum on Nabble is no longer linked to the SPSSX-L listserv administered by UGA (https://listserv.uga.edu/).
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Re: how to develop probit or multilogit models for accident data

Rich Ulrich
In reply to this post by ramesh
The general computing convention for 0/1  is that 0 is False, 1 is True;
your data has that reversed.  This will be vastly confusing to any
professional who looks at your data or results.

 - In order to minimize confusion among the people who gave you
the data (if that matters), instead of merely reversing your 0/1 scores
(by subtracting each from 1), it could be wiser to RECODE the 0s as 2s.
That way, they can KNOW that a value of 1.5  does not arise from some
use of 0/1.  If I simply reversed the scores, I would also insist on changing
the original variable names, if anyone else had ever seen or used the data.

A two-group prediction is done with simple discriminant function or
with Logistic regression.  You might consider an interaction term or two,
especially if there are any strong main effects observed.

However, your file has only 88 fatalities -- that places an implicit limit on
how many variables you can safely use in one model of about 9... at most.
(If you know what you are doing, you can try more.  But if you knew that,
you would not be asking what you are asking.)

--
Rich Ulrich


> Date: Thu, 4 Apr 2013 07:01:30 -0700

> From: [hidden email]
> Subject: how to develop probit or multilogit models for accident data
> To: [hidden email]
>
> i had given the following coding
> severity sv Rear end head on swipe lanewid rural drvage female alcohol
> 1 1 0 1 1 7 1 21 1 1
> 0 1 1 1 0 7 1 20 1 1
> 1 1 0 1 1 7 1 27 1 1
>
> as final_coded.xls
> <http://spssx-discussion.1045642.n5.nabble.com/file/n5719262/final_coded.xls>
>
> severity single vehicle rear end head on swipe rural female alcohol
> fatal=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0 yes=0
> non fatal=1 no=1 no=1 no=1 no=1 no=1 no=1 no=1
>
> how to develop model for different types of collision based on severity
>
> pl. help me
>
> ...