Formatting p-values less than 0.0001

Discussion:

(too old to reply)

Bob Abelson

2006-03-20 18:33:33 UTC

First let me start by saying I'm stuck with SAS Version 8.2 for now.

I use the pvalue8.4 format to display p-values. We would like to see
p-values less than 0.0001 displayed as "<0.0001" instead of "<.0001". Is
that a possibility with the pvalue format?

Thanks,

Bob Abelson
HGSI
240 314 4400 x1374
***@hgsi.com

David L Cassell

2006-03-20 18:57:59 UTC

Permalink

Post by Bob Abelson
First let me start by saying I'm stuck with SAS Version 8.2 for now.
I use the pvalue8.4 format to display p-values. We would like to see
p-values less than 0.0001 displayed as "<0.0001" instead of "<.0001". Is
that a possibility with the pvalue format?

Even if you had SAS 9.1.3 I don't think the PVALUEw.d format would do
this.

As I understand it, PVALUE. prints the less-than-.0001 values with no
leading decimal point. That is, if you ask for PVALUEw.d and the
p-value is less than 1E-d then you get "<.0...01" with d-1 zeroes.

So you may have to create your own picture format for this one.

HTH,
David
--
David L. Cassell
mathematical statistician
Design Pathways
3115 NW Norwood Pl.
Corvallis OR 97330

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Venky Chakravarthy

2006-03-20 19:04:42 UTC

Permalink

Bob,

Since p values take the range 0-1, you only have small subset to consider
for creating your own format. Would something like this work? Adjust when
you have to conside another w.d.

proc format ;
value mypval 0.0001 - 1 = [pvalue8.4]
0 - <1e-4 = "<0.0001" ;
run ;

data _null_ ;
input x ;
put x = : mypval. ;
cards ;
1
0.01
0.001
0.0001
0.000001
0.00001
run ;

Bob Abelson

2006-03-20 19:14:10 UTC

Permalink

Venky,

This works perfectly if I change the nested format to pvalue7.4. Thanks!

Bob Abelson
HGSI
240 314 4400 x1374
***@hgsi.com

Venky Chakravarthy <***@HOTMAIL.COM>
03/20/2006 02:04 PM

To: SAS-***@LISTSERV.UGA.EDU, Bob Abelson <***@HGSI.COM>
cc:
Subject: Re: Formatting p-values less than 0.0001

Venky Chakravarthy

2006-03-20 21:24:57 UTC

Permalink

Bob,

I think 6.4 should be sufficient. That is 4 for the places after the
decimal, 1 for the decimal itself and 1 for the integer value. So 6.4 should
suffice.

Venky

Post by Bob Abelson
Venky,
This works perfectly if I change the nested format to pvalue7.4. Thanks!
Bob Abelson
HGSI
240 314 4400 x1374
03/20/2006 02:04 PM
Subject: Re: Formatting p-values less than 0.0001

Bob,
Since p values take the range 0-1, you only have small subset to consider
for creating your own format. Would something like this work? Adjust when
you have to conside another w.d.
proc format ;
value mypval 0.0001 - 1 = [pvalue8.4]
0 - <1e-4 = "<0.0001" ;
run ;
data _null_ ;
input x ;
put x = : mypval. ;
cards ;
1
0.01
0.001
0.0001
0.000001
0.00001
run ;

Bob Abelson

2006-03-20 21:57:46 UTC

Permalink

Venky,

Actually, it's more of an alignment issue. Since the output will be right
justified, the decimal points will align with 7.4.

Bob Abelson
HGSI
240 314 4400 x1374
***@hgsi.com

Venky Chakravarthy <***@HOTMAIL.COM>
03/20/2006 04:24 PM

To: SAS-***@LISTSERV.UGA.EDU, Bob Abelson <***@HGSI.COM>
cc:
Subject: Re: Formatting p-values less than 0.0001

Bob,

I think 6.4 should be sufficient. That is 4 for the places after the
decimal, 1 for the decimal itself and 1 for the integer value. So 6.4
should
suffice.

Venky

Bob,
Since p values take the range 0-1, you only have small subset to consider
for creating your own format. Would something like this work? Adjust when
you have to conside another w.d.
proc format ;
value mypval 0.0001 - 1 = [pvalue8.4]
0 - <1e-4 = "<0.0001" ;
run ;
data _null_ ;
input x ;
put x = : mypval. ;
cards ;
1
0.01
0.001
0.0001
0.000001
0.00001
run ;

Venky Chakravarthy

2006-03-20 22:17:30 UTC

Permalink

Bob,

I had guessed that you probably wanted a wide enough specification for
proper alignment but I missed counting the place for the less than sign (<).

Venky

Post by Bob Abelson
Venky,
Actually, it's more of an alignment issue. Since the output will be right
justified, the decimal points will align with 7.4.
Bob Abelson
HGSI
240 314 4400 x1374
03/20/2006 04:24 PM
Subject: Re: Formatting p-values less than 0.0001
Bob,
I think 6.4 should be sufficient. That is 4 for the places after the
decimal, 1 for the decimal itself and 1 for the integer value. So 6.4
should
suffice.
Venky

Bob,
Since p values take the range 0-1, you only have small subset to consider
for creating your own format. Would something like this work? Adjust when
you have to conside another w.d.
proc format ;
value mypval 0.0001 - 1 = [pvalue8.4]
0 - <1e-4 = "<0.0001" ;
run ;
data _null_ ;
input x ;
put x = : mypval. ;
cards ;
1
0.01
0.001
0.0001
0.000001
0.00001
run ;