Frequently Asked Questions
This page contains some of the frequetly asked questions. If you don't find the answer to your question, please email us.
- Do you offer your datasets in Excel?
- What is a SAS-TPT file and how can I open it?
- What is a SPSS-Portable file and how can I open it?
- What year do your data belong to?
- Do you survey the head of the household or the family living back in Mexico?
- How do you define "head of the household"?
- How often do you release new data?
- I'm interested in using the MMP, but I don't see the link to register.
- How can I merge your datasets (i.e. PERS with HOUSE)?
- My dataset has a value of 9998.9999. Why is that?
- What is the difference between your missing value and your code 9999?
- Was there ever a change in your categories for the use of remittances/savings?
- I merged PERS and HOUSE and I have about 376 persons with no observation in HOUSE. Did I do something wrong?
- How can I access your publications?
- I'm looking for statistics on remittances
1. Do you offer your datasets in Excel?
No, some of our databases are too large for Excel. Excel can only handle up to 1,048,576 observations. Thus, if you are interested in reading our datasets in Excel, you may download them using the CSV format. Note that the LIFE file will be incomplete during this process because LIFE file is larger than the number of observations Excel handles.
In addition to CSV format, we also offer our datasets in SAS for Windows, SPSS for Windows, and Stata. (Top)
2. What is a SAS-TPT file and how can I open it?
Until MMP124, we offered our SAS data in TPT format which is a compressed form of sas7dbat. In order to open it, you need to use StatTranfer and convert it from TPT to SAS file. However, starting with MMP128 in March 2010, we are now offering our SAS files in sas7dbat. You no longer need to do this conversion. (Top)
3. ¿What is a SPSS-POR and how can I open it?
Until MMP124, we offered our SPSS data in portable format which is a compressed form of sav files. In order to open it, you need to open SPSS first, then open the file, and save it with a SAV format. However, starting with MMP128 in March 2010, we are now offereing our SPSS files in SAV. you no longer need to do this conversion. (Top)
4. What year do your data belong to?
Until today, the MMP has interviewed 150 communities. The first 4 communities were interviewed in 1982. Since 1987, every year, we interview an average of 4 communities. The last 7 communities were interviewed in January 2014. Appendix A offers the list of communities and the year of interview. (Top)
5. Do you survey the head of the household or the family living back in Mexico?
The ideal is to interview the head of the household. However, if the head of the household is not at home during fieldwork, we interview the spouse who is most likely to know all his/her life-history. (Top)
6. How do you define "head of the household"?
You will find the definition of the "household head" on page 3 and 4 of our interviewer's manual. (Top)
7. How often do you release new data?
In the last 4 years, we have been able to do a release every year. We interview communities in January, and it takes us about 15 months to capture and process our datasets and make them available to the public. (Top)
8. I'm interested in using the MMP, but I don't see the link to register.
If this is the first time you download our datasets, you must register at OPR's Data Archive. Once you input your email, OPR will send you an email with a temporary password. Then, you'll be able to access all of our datasets free of charge. (Top)
9. How can I merge your datasets (i.e. PERS with HOUSE)?
All of our datasets have the variables COMMUN (comunity) and HHNUM (household number) in common. You need to create an ID with those two variables. The ID will follow this idea: COMMUN + (HHNUM*10000). COMMUN has 3 digits and HHNUM has 4; miltiply HHNUM by 10,000 and add it to COMMUN to obtain such ID. Then, sort both files by ID and merge them by ID. (Top)
10. My dataset has a value of 9998.9999. Why is that?
This only occurs in SPSS files. We process all of our data in SAS. Then, we convert our files to SPSS and Stata. We believe that the files SPSS files get corrupt on this step. This problem has not been reported when converting files from SAS to Stata. If you encounter these values, just modify them to 9999. (Top)
11. What is the difference between a missing value and your code 9999?
Our code 9999 stands for "unknown"; this means that the information for such variable is unknown at the time of the survey. Our missing value is only present on those variables that have been added in later versions of the ethnosurvey. One example is found on the health variables. If you notice, missing value is reported for communities 1 to 114, and this is because health variables were added starting community 115 until today. (Top)
12. Was there ever a change in your categories for the use of remittances/savings?
Yes; if you take a look at our page where we present our surveys' comparisons, you'll notice that in the first version we didn't have 16 categories. Those categories were then adjusted for later versions. It is important to note that the MMP has tried to maintain the core of the ethnosurvey; some changes have been made to keep up with the migratory reality. Any modification to the survey is carefully reviewed before implementing it. (Top)
13.I merged PERS and HOUSE and I have about 376 persons with no observations in HOUSE. Did I do something wrong?
No, you did not. Those observations belong to households interviewed back in 1982 in the U.S. For some reason, those data have been lost at the HOUSE level, but it is available at the PERS level. Just assign unknown value (9999) at the household level before running your analysis. (Top)
14. How can I access your publications?
We offer some articles in PDF at our publications page. However, you'll find most of the articles through your library through JSTOR and Worldcat. Due to copyright, we cannot offer them through this website. (Top)
15. I'm looking for statistics on remittances
The MMP offers data with information on remittances so you can do your own analysis. The only analysis we offer is through our results page. (Top)