I have two variabled called "prean" and "pa_kum" that contain missing values. These missing values i would like to replace by 0 (zero). What command can i use to do this?
Thanks in advance for your support. Regards 
<> ************* clear* input myvar 1 3 5 . 3 6 7 end recode myvar (mis = 0) l ************* HTH Martin Ursprüngliche Nachricht Von: [hidden email] [mailto:[hidden email]] Im Auftrag von Hobst Gesendet: Montag, 9. August 2010 10:55 An: [hidden email] Betreff: st: Replace missing values by 0 I have two variabled called "prean" and "pa_kum" that contain missing values. These missing values i would like to replace by 0 (zero). What command can i use to do this? Thanks in advance for your support. Regards  View this message in context: http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0tp5388239 p5388239.html Sent from the Statalist mailing list archive at Nabble.com. * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
In reply to this post by Hobst
mvencode
T 2010/8/9 Hobst <[hidden email]>: > I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? > > Thanks in advance for your support. Regards >  > View this message in context: http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0tp5388239p5388239.html > Sent from the Statalist mailing list archive at Nabble.com. > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/statalist/faq > * http://www.ats.ucla.edu/stat/stata/ >  To every ωconsistent recursive class κ of formulae there correspond recursive class signs r, such that neither v Gen r nor Neg(v Gen r) belongs to Flg(κ) (where v is the free variable of r). * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
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In reply to this post by Hobst
On Mon, Aug 9, 2010 at 8:55 AM, Hobst <[hidden email]> wrote:
> I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } ...is one way to skin this cat. > Thanks in advance for your support. Regards This is a very basic question though. You may well benefit from reading the Users Guide and/or taking the Stata Net Course 101 : Introduction to Stata (see http://www.stata.com/netcourse/nc101.html). Neil  "One should as a rule, respect public opinion in so far as is necessary to avoid starvation and to keep out of prison, but anything that goes beyond this is voluntary submission to an unnecessary tyranny, and is likely to interfere with happiness in all kinds of ways..."  Bertrand Russell Email  [hidden email] Website  http://slack.ser.man.ac.uk/ Photos  http://www.flickr.com/photos/slackline/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
<> Stata even forgives the missing blank after if! Amazing! ************* clear* inp prean pa_kurn 2 3 . 5 . 3 . . 4 5 end foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } l ************* One problem with this "firstprinciples" approach is that you have to compare explicitly with all missing values, i.e. also the extended ones. recode can help avoid this problem. HTH Martin Ursprüngliche Nachricht Von: [hidden email] [mailto:[hidden email]] Im Auftrag von Neil Shephard Gesendet: Montag, 9. August 2010 11:01 An: [hidden email] Betreff: Re: st: Replace missing values by 0 On Mon, Aug 9, 2010 at 8:55 AM, Hobst <[hidden email]> wrote: > I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } ...is one way to skin this cat. > Thanks in advance for your support. Regards This is a very basic question though. You may well benefit from reading the Users Guide and/or taking the Stata Net Course 101 : Introduction to Stata (see http://www.stata.com/netcourse/nc101.html). Neil  "One should as a rule, respect public opinion in so far as is necessary to avoid starvation and to keep out of prison, but anything that goes beyond this is voluntary submission to an unnecessary tyranny, and is likely to interfere with happiness in all kinds of ways..."  Bertrand Russell Email  [hidden email] Website  http://slack.ser.man.ac.uk/ Photos  http://www.flickr.com/photos/slackline/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
In reply to this post by Tirthankar Chakravarty
I have one specific and one general comment here.
Specifically, Martin is correct to underline that . is not the only missing value, but the loop in question is easily fixed by foreach x of varlist prean pa_kurn{ replace `x' = 0 if missing(x) } Generally, a minimal search missing points to several resources. One of the very first entries, to [I] missing values, answers this question comprehensively, so it is difficult to see why it was felt necessary to send it to Statalist. Nick [hidden email] Martin Weiss ============ Stata even forgives the missing blank after if! Amazing! ************* clear* inp prean pa_kurn 2 3 . 5 . 3 . . 4 5 end foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } l ************* One problem with this "firstprinciples" approach is that you have to compare explicitly with all missing values, i.e. also the extended ones. recode can help avoid this problem. Neil Shephard ============= foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } ...is one way to skin this cat. Martin Weiss ============ clear* input myvar 1 3 5 . 3 6 7 end recode myvar (mis = 0) l Tirthankar Chakravarty mvencode Tobias Friedli > I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
Should be
replace `x' = 0 if missing(`x') Nick [hidden email] Original Message From: Nick Cox I have one specific and one general comment here. Specifically, Martin is correct to underline that . is not the only missing value, but the loop in question is easily fixed by foreach x of varlist prean pa_kurn{ replace `x' = 0 if missing(x) } Generally, a minimal search missing points to several resources. One of the very first entries, to [I] missing values, answers this question comprehensively, so it is difficult to see why it was felt necessary to send it to Statalist. Nick [hidden email] Martin Weiss ============ Stata even forgives the missing blank after if! Amazing! ************* clear* inp prean pa_kurn 2 3 . 5 . 3 . . 4 5 end foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } l ************* One problem with this "firstprinciples" approach is that you have to compare explicitly with all missing values, i.e. also the extended ones. recode can help avoid this problem. Neil Shephard ============= foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } ...is one way to skin this cat. Martin Weiss ============ clear* input myvar 1 3 5 . 3 6 7 end recode myvar (mis = 0) l Tirthankar Chakravarty mvencode Tobias Friedli > I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
<> ************* replace `x' = 0 if (`x' >= .) ************* might also do the trick. It is important, in all solutions offered in this thread, to make sure you feed them only numeric variables. Nick`s mi() function does cover strings as well, but the first part of the replace command is then no longer correct. HTH Martin Ursprüngliche Nachricht Von: [hidden email] [mailto:[hidden email]] Im Auftrag von Nick Cox Gesendet: Montag, 9. August 2010 17:20 An: [hidden email] Betreff: RE: st: Replace missing values by 0 Should be replace `x' = 0 if missing(`x') Nick [hidden email] Original Message From: Nick Cox I have one specific and one general comment here. Specifically, Martin is correct to underline that . is not the only missing value, but the loop in question is easily fixed by foreach x of varlist prean pa_kurn{ replace `x' = 0 if missing(x) } Generally, a minimal search missing points to several resources. One of the very first entries, to [I] missing values, answers this question comprehensively, so it is difficult to see why it was felt necessary to send it to Statalist. Nick [hidden email] Martin Weiss ============ Stata even forgives the missing blank after if! Amazing! ************* clear* inp prean pa_kurn 2 3 . 5 . 3 . . 4 5 end foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } l ************* One problem with this "firstprinciples" approach is that you have to compare explicitly with all missing values, i.e. also the extended ones. recode can help avoid this problem. Neil Shephard ============= foreach x of varlist prean pa_kurn{ replace `x' = 0 if(`x' == .) } ...is one way to skin this cat. Martin Weiss ============ clear* input myvar 1 3 5 . 3 6 7 end recode myvar (mis = 0) l Tirthankar Chakravarty mvencode Tobias Friedli > I have two variabled called "prean" and "pa_kum" that contain missing values. > These missing values i would like to replace by 0 (zero). What command can i > use to do this? * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
In reply to this post by Hobst
In all of the discussion of this query, nobody has asked why it is important to do this? If you are computing means, the 0 values will distort the mean (or median if enough), and if you simply want to ignore zeros with "if x~=0") retaining the missing value will do this automatically.
I am unsure if I've ever had a reason to convert missing values to a numeric value, but have had many times when the 9 for missing (or whatever) had to be set to "." Tony Peter A. Lachenbruch Department of Public Health Oregon State University Corvallis, OR 97330 Phone: 5417373832 FAX: 5417374001 Original Message From: [hidden email] [mailto:[hidden email]] On Behalf Of Hobst Sent: Monday, August 09, 2010 1:55 AM To: [hidden email] Subject: st: Replace missing values by 0 I have two variabled called "prean" and "pa_kum" that contain missing values. These missing values i would like to replace by 0 (zero). What command can i use to do this? Thanks in advance for your support. Regards  View this message in context: http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0tp5388239p5388239.html Sent from the Statalist mailing list archive at Nabble.com. * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
Tony,
Sometimes data, especially count data, are stored in a spreadsheet where a blank cell indicates a zero value. For example, if the data are handentered and there are a lot of zero values, it is more efficient not to enter a zero, and many spreadsheet functions treat the blank cell as a zero value. However, if you paste or insheet these data into Stata, the blank cells are encoded as missing values. In this case it is necessary to convert the missing values to zeroes. David  David Radwin Research Associate MPR Associates, Inc. 2150 Shattuck Ave., Suite 800 Berkeley, CA 94704 Phone: 5108494942 Fax: 5108490794 www.mprinc.com > Original Message > From: [hidden email] [mailto:owner > [hidden email]] On Behalf Of Lachenbruch, Peter > Sent: Monday, August 09, 2010 2:59 PM > To: '[hidden email]' > Subject: st: RE: Replace missing values by 0 > > In all of the discussion of this query, nobody has asked why it is > important to do this? If you are computing means, the 0 values will > distort the mean (or median if enough), and if you simply want to ignore > zeros with "if x~=0") retaining the missing value will do this > automatically. > > I am unsure if I've ever had a reason to convert missing values to a > numeric value, but have had many times when the 9 for missing (or > whatever) had to be set to "." > > Tony > > Peter A. Lachenbruch > Department of Public Health > Oregon State University > Corvallis, OR 97330 > Phone: 5417373832 > FAX: 5417374001 > > > Original Message > From: [hidden email] [mailto:owner > [hidden email]] On Behalf Of Hobst > Sent: Monday, August 09, 2010 1:55 AM > To: [hidden email] > Subject: st: Replace missing values by 0 > > I have two variabled called "prean" and "pa_kum" that contain missing > values. > These missing values i would like to replace by 0 (zero). What command > i > use to do this? > > Thanks in advance for your support. Regards >  > View this message in context: > http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0 > tp5388239p5388239.html > Sent from the Statalist mailing list archive at Nabble.com. * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
But the original question was about missing values being represented as 0.
Use of a blank cell for 0 allows the confusion of missing and true 0. At any rate, if you want to code missing as 0 that's a problem to my mind. Tony Peter A. Lachenbruch Department of Public Health Oregon State University Corvallis, OR 97330 Phone: 5417373832 FAX: 5417374001 Original Message From: [hidden email] [mailto:[hidden email]] On Behalf Of David Radwin Sent: Monday, August 09, 2010 3:29 PM To: [hidden email] Subject: st: RE: RE: Replace missing values by 0 Tony, Sometimes data, especially count data, are stored in a spreadsheet where a blank cell indicates a zero value. For example, if the data are handentered and there are a lot of zero values, it is more efficient not to enter a zero, and many spreadsheet functions treat the blank cell as a zero value. However, if you paste or insheet these data into Stata, the blank cells are encoded as missing values. In this case it is necessary to convert the missing values to zeroes. David  David Radwin Research Associate MPR Associates, Inc. 2150 Shattuck Ave., Suite 800 Berkeley, CA 94704 Phone: 5108494942 Fax: 5108490794 www.mprinc.com > Original Message > From: [hidden email] [mailto:owner > [hidden email]] On Behalf Of Lachenbruch, Peter > Sent: Monday, August 09, 2010 2:59 PM > To: '[hidden email]' > Subject: st: RE: Replace missing values by 0 > > In all of the discussion of this query, nobody has asked why it is > important to do this? If you are computing means, the 0 values will > distort the mean (or median if enough), and if you simply want to ignore > zeros with "if x~=0") retaining the missing value will do this > automatically. > > I am unsure if I've ever had a reason to convert missing values to a > numeric value, but have had many times when the 9 for missing (or > whatever) had to be set to "." > > Tony > > Peter A. Lachenbruch > Department of Public Health > Oregon State University > Corvallis, OR 97330 > Phone: 5417373832 > FAX: 5417374001 > > > Original Message > From: [hidden email] [mailto:owner > [hidden email]] On Behalf Of Hobst > Sent: Monday, August 09, 2010 1:55 AM > To: [hidden email] > Subject: st: Replace missing values by 0 > > I have two variabled called "prean" and "pa_kum" that contain missing > values. > These missing values i would like to replace by 0 (zero). What command > i > use to do this? > > Thanks in advance for your support. Regards >  > View this message in context: > http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0 > tp5388239p5388239.html > Sent from the Statalist mailing list archive at Nabble.com. * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
In reply to this post by David Radwin2

In many cases, skip patterns in questionnaires leave behind missing values, either 9's or .'s. If you told the interviewer that you didn't do behavior X in the past year, you won't be asked how many times you did X in the past 30 days. The missing value for 30day behavior X really does represent a zero. Dave ==================================== David C. Bell Professor of Sociology Indiana University Purdue University Indianapolis (IUPUI) (317) 2781336 ==================================== On Aug 9, 2010, at 6:29 PM, David Radwin wrote: > Tony, > > Sometimes data, especially count data, are stored in a spreadsheet where a > blank cell indicates a zero value. For example, if the data are > handentered and there are a lot of zero values, it is more efficient not > to enter a zero, and many spreadsheet functions treat the blank cell as a > zero value. > > However, if you paste or insheet these data into Stata, the blank cells > are encoded as missing values. In this case it is necessary to convert the > missing values to zeroes. > > David > >  > David Radwin > Research Associate > MPR Associates, Inc. > 2150 Shattuck Ave., Suite 800 > Berkeley, CA 94704 > Phone: 5108494942 > Fax: 5108490794 > > www.mprinc.com > > >> Original Message >> From: [hidden email] [mailto:owner >> [hidden email]] On Behalf Of Lachenbruch, Peter >> Sent: Monday, August 09, 2010 2:59 PM >> To: '[hidden email]' >> Subject: st: RE: Replace missing values by 0 >> >> In all of the discussion of this query, nobody has asked why it is >> important to do this? If you are computing means, the 0 values will >> distort the mean (or median if enough), and if you simply want to ignore >> zeros with "if x~=0") retaining the missing value will do this >> automatically. >> >> I am unsure if I've ever had a reason to convert missing values to a >> numeric value, but have had many times when the 9 for missing (or >> whatever) had to be set to "." >> >> Tony >> >> Peter A. Lachenbruch >> Department of Public Health >> Oregon State University >> Corvallis, OR 97330 >> Phone: 5417373832 >> FAX: 5417374001 >> >> >> Original Message >> From: [hidden email] [mailto:owner >> [hidden email]] On Behalf Of Hobst >> Sent: Monday, August 09, 2010 1:55 AM >> To: [hidden email] >> Subject: st: Replace missing values by 0 >> >> I have two variabled called "prean" and "pa_kum" that contain missing >> values. >> These missing values i would like to replace by 0 (zero). What command > can >> i >> use to do this? >> >> Thanks in advance for your support. Regards >>  >> View this message in context: >> http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0 >> tp5388239p5388239.html >> Sent from the Statalist mailing list archive at Nabble.com. > > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/statalist/faq > * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
be careful  while what you say is true, you also won't be asked if
you were happy doing "x"  and 0 is not correct for that I definitely agree with Tony that just mindlessly doing what the OP asked is very dangerous Rich On 8/10/10 12:13 PM, David Bell wrote: >  > In many cases, skip patterns in questionnaires leave behind missing values, either 9's or .'s. If you told the interviewer that you didn't do behavior X in the past year, you won't be asked how many times you did X in the past 30 days. The missing value for 30day behavior X really does represent a zero. > > Dave > ==================================== > David C. Bell > Professor of Sociology > Indiana University Purdue University Indianapolis (IUPUI) > (317) 2781336 > ==================================== > > > > > On Aug 9, 2010, at 6:29 PM, David Radwin wrote: > >> Tony, >> >> Sometimes data, especially count data, are stored in a spreadsheet where a >> blank cell indicates a zero value. For example, if the data are >> handentered and there are a lot of zero values, it is more efficient not >> to enter a zero, and many spreadsheet functions treat the blank cell as a >> zero value. >> >> However, if you paste or insheet these data into Stata, the blank cells >> are encoded as missing values. In this case it is necessary to convert the >> missing values to zeroes. >> >> David >> >>  >> David Radwin >> Research Associate >> MPR Associates, Inc. >> 2150 Shattuck Ave., Suite 800 >> Berkeley, CA 94704 >> Phone: 5108494942 >> Fax: 5108490794 >> >> www.mprinc.com >> >> >>> Original Message >>> From: [hidden email] [mailto:owner >>> [hidden email]] On Behalf Of Lachenbruch, Peter >>> Sent: Monday, August 09, 2010 2:59 PM >>> To: '[hidden email]' >>> Subject: st: RE: Replace missing values by 0 >>> >>> In all of the discussion of this query, nobody has asked why it is >>> important to do this? If you are computing means, the 0 values will >>> distort the mean (or median if enough), and if you simply want to ignore >>> zeros with "if x~=0") retaining the missing value will do this >>> automatically. >>> >>> I am unsure if I've ever had a reason to convert missing values to a >>> numeric value, but have had many times when the 9 for missing (or >>> whatever) had to be set to "." >>> >>> Tony >>> >>> Peter A. Lachenbruch >>> Department of Public Health >>> Oregon State University >>> Corvallis, OR 97330 >>> Phone: 5417373832 >>> FAX: 5417374001 >>> >>> >>> Original Message >>> From: [hidden email] [mailto:owner >>> [hidden email]] On Behalf Of Hobst >>> Sent: Monday, August 09, 2010 1:55 AM >>> To: [hidden email] >>> Subject: st: Replace missing values by 0 >>> >>> I have two variabled called "prean" and "pa_kum" that contain missing >>> values. >>> These missing values i would like to replace by 0 (zero). What command >> can >>> i >>> use to do this? >>> >>> Thanks in advance for your support. Regards >>>  >>> View this message in context: >>> http://statalist.1588530.n2.nabble.com/Replacemissingvaluesby0 >>> tp5388239p5388239.html >>> Sent from the Statalist mailing list archive at Nabble.com. * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
In reply to this post by Lachenbruch, Peter
I'd put it this way.
If blanks that should be zeros are interpreted by Stata on input as missings, then it's appropriate to map those missings to zeros before analysis. It's easy enough to show that this can happen, e.g. by copy and paste from a spreadsheet to Stata's data editor. Clearly, anyone doing this should be certain that it is exactly what they want. If there are other genuine missings, replacing them by zero is a very bad idea. Nick [hidden email] Lachenbruch, Peter But the original question was about missing values being represented as 0. Use of a blank cell for 0 allows the confusion of missing and true 0. At any rate, if you want to code missing as 0 that's a problem to my mind. * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/ 
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