Data Coding and File Construction

After the ethnosurvey questionnaires are completed and revised, data are entered in Mexico. The entry programs perform initial screening, range checks, and simple tests for logical consistency. The preliminary files are then transferred to Princeton University, where additional data cleaning is performed, numeric codes are assigned to occupations and places, and the final data sets are assembled into six primary data files, each providing a unique perspective of Mexican migrants, their families, and their experiences. SIX primary files have been created, each corresponding to a different unit of analysis: PERS, MIG, MIGOTHER, HOUSE, LIFE and SPOUSE. Data at the community level have been compiled in the file: COMMUN.

Go to our Data Overview to learn more about our databases.


The MMP database provides community- and sample-specific weights. For each community, you will see a single weight for all the households in the home country sample and another weight for all the households in the US sample.

When working with pooled data from multiple communities, these weights give you the option to adjust your estimates in order to take into account the relative sizes of all the sampling frames. Whether you will need to weight your estimates or not will depend on what your goal is. The document below contains a detailed explanation on our computation of the weights, and suggests criteria to use them or disregard them.

MMP and LAMP weights