The Mexico EquityTool country factsheet and file downloads on this page are licensed under CC BY-NC 4.0
Source data: Mexico MICS 2015
# of survey questions in full wealth index: 44
# of variables in full index: 120
# of survey questions in EquityTool: 12
# of variables in EquityTool: 13
Questions:
Question | Option 1 | Option 2 | Option 3 | |
Q1 | Does your household have… a water heater? | Yes | No | |
Q2 | … a microwave? | Yes | No | |
Q3 | … a washing machine? | Yes | No | |
Q4 | … a cistern? | Yes | No | |
Q5 | … internet service? | Yes | No | |
Q6 | … a non-mobile telephone? | Yes | No | |
Q7 | … paid T.V. service? | Yes | No | |
Q8 | … a computer? | Yes | No | |
Q9 | Does any member of your household own a car or truck? | Yes | No | |
Q10 | What is the main material of the roof of your household? | Cement or concrete | Other | |
Q11 | What is the main material of the floor of your household? | Mosaic, Marble or Ceramic | Cement | Other |
Q12 | What type of toilet facility do members of your household usually use? | Flush to piped sewer system (not shared with others) | Other |
Technical notes:
The standard simplification process was applied to achieve high agreement with the original wealth index. Kappa was greater than 0.75 for the national and urban indices. Details on the standard process can be found in this article. The data used to identify important variables comes from factor weights derived from the reconstruction of the MICS Wealth Index using analytical syntax provided by UNICEF. The MICS wealth index for Mexico is constructed using the same approach as the DHS Wealth Index. More information about how the DHS Wealth Index is constructed can be found here. Factor weights used in the construction of the Mexico EquityTool are available upon request.
Level of agreement:
National Population (n=10,760) | Urban only population (n=7,240) | |
% agreement | 84.8% | 84.8% |
Kappa statistic | 0.762 | 0.762 |
Respondents in the original dataset were divided into three groups for analysis – those in the 1st and 2nd quintiles (poorest 40%), those in the 3rd quintile, and those in the 4th and 5th quintiles (richest 40%). After calculating their wealth using the simplified index, they were again divided into the same three groups for analysis against the original data in the full MICS wealth index. Agreement between the original data and our simplified index is presented above.
What does this mean?
When shortening and simplifying the index to make it easier for programs to use to assess equity, it no longer matches the original index with 100% accuracy. At an aggregate level, this error is minimal, and this methodology was deemed acceptable for programmatic use by an expert panel. However, for any given individual, especially those already at a boundary between two quintiles, the quintile the EquityTool assigns them to may differ to their quintile according to the original MICS wealth index.
The graph below illustrates the difference between the EquityTool generated index and the full MICS wealth index. Among all of those people (20% of the population) originally identified as being in the poorest quintile, approximately 15.2 % are still identified as being in the poorest quintile when we use the simplified index. However, approximately 4.3 % of people are now classified as being in Quintile 2. From a practical standpoint, all of these people are relatively poor. Yet, it is worthwhile to understand that the simplified index of 12 questions produces results that are not identical to using all 44 questions in the original survey.
The following table provides the same information on the movement between national quintiles when using the EquityTool versus the original MICS wealth index:
EquityTool National Quintiles | |||||||
Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | Total | ||
Original MICS National Quintiles | Quintile 1 | 15.2% | 4.3% | 0.4% | 0.1% | 0.1% | 20% |
Quintile 2 | 4.8% | 11.4% | 3.3% | 0.3% | 0.1% | 20% | |
Quintile 3 | 0.0% | 4.4% | 12.6% | 2.8% | 0.2% | 20% | |
Quintile 4 | 0.0% | 0.0% | 3.6% | 14.3% | 2.1% | 20% | |
Quintile 5 | 0.0% | 0.0% | 0.0% | 3.2% | 16.8% | 20% | |
Total | 20.1% | 20.1% | 20.0% | 20.1% | 19.4% | 100% |
The following graph provides information on the movement between urban quintiles when using the EquityTool versus the original MICS wealth index:
The following table provides the same information on the movement between urban quintiles when using the EquityTool versus the original MICS wealth index:
EquityTool Urban Quintiles | |||||||
Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | Total | ||
Original MICS Urban Quintiles | Quintile 1 | 16.3% | 3.2% | 0.3% | 0.1% | 0.0% | 20% |
Quintile 2 | 3.7% | 12.9% | 3.0% | 0.3% | 0.2% | 20% | |
Quintile 3 | 0.0% | 4.0% | 12.6% | 3.3% | 0.2% | 20% | |
Quintile 4 | 0.0% | 0.0% | 3.9% | 13.2% | 2.8% | 20% | |
Quintile 5 | 0.0% | 0.0% | 0.0% | 3.4% | 16.6% | 20% | |
Total | 20.0% | 20.1% | 19.9% | 20.2% | 19.8% | 100% |
Data interpretation considerations:
Metrics for Management provides technical assistance services to those using the EquityTool, or wanting to collect data on the wealth of their program beneficiaries. Please contact support@equitytool.org and we will assist you.
[1] From povertydata.worldbank.org, reporting Poverty headcount ratio at $1.90/day at 2011 international prices.
[2] From the Mexico dataset household recode, available at http://www.mics.unicef.org/surveys