Assessing the impact, in terms of health, both mental and physical, of governmental programs designed to improve the well-being of their citizens is key in order to enhance the policy-making perspective in such programs. In developing countries, where the percentage of the population living in extreme poverty is great, these programs become a matter of national priority.

Piso Firme (or "firm floor" in English) is a large scale Mexican program which aimed to propose to households to replace their dirt floors by cement floors for free. Families were proposed up to 50 square meters of concrete cement floors of a value of about 1,500 Mexican pesos, which was aproximately 150 dollars. On the map below, one can see that dirt floors are numerous in the twin cities of Gómez Palacios and Torreón (which will be the regions of interest for the study). Some clusters of household have more than 75% of dirt floors.

Another important reason to propose Piso Firme to families is the high proportion of households below the poverty line. You can observe them on the map below. Financial hardship may make it difficult for these families to afford the dirt floor replacements, thus the program is of great significance in this regard.

In the paper "Housing, Health, and Happiness" by Cataneo, M. et. al. (2009), the health impacts of the Piso Firme program are analyzed and assessed. The aim of this study was to measure the impact on the health of young children, and the feeling of happiness of their caretakers (usually their mothers) by that program. Measurements for the incidence of parasitic infestations, diarrhea, cognitive development, and anemia in children, and measurements in increased satisfaction with their household and quality of life, depression and stress scales in the adults were used to perform several regression analyses to determine whether or not the program has a significant impact in such factors.

Below you can see the repartition of data samples between the states of Durango and Coahuila. Coahuila was the first state to received Piso Firme. When the data was collected, households from Gómez Palacios and Lerdo (in the state of Durango) did not benefit yet from Piso Firme. In their paper, Cataneo, M. et. al. could measure the benefits of Piso Firme in Gómez Palacios by comparing the mental and physical health indicators with the ones they observed in Torreón. Authors collected their data in households through a survey in 2005 and the data was supplemented with the 2000 Mexican census.

One of the results from this paper is the observation of significant positive effects on maternal happiness in households that were proposed Piso Firme, such as a decrease of perceived stress and depression, and an increase in house satisfaction and quality of life.

We know that Piso Firme improves the well-being of caretakers in these households by installing cement floors. A maximum number of people should benefit from it. Why doesn't the government create campaigns to promote installation of cement floors in households ? This could be a very cost-effective action to improve general well-being in the region of interest as households would invest themselves in their housing to (hopefully) observe these benefits. But these households have limited economic ressources. Therefore, if we want to advise households on what improvement they should invest in, we need to make sure that households who invested by themselves in cement floors received similar benefits as households who were proposed Piso Firme. Thus, we will try to determine if households that decided to install cement floors without aid from the government also show the same mental health and satisfaction improvements.

The data used in the following study comes from the dataset produced by Cataneo, M. et. al.

To measure mental health we consider 5 variables :

• The satisfaction with floor quality
• The satisfaction with house quality
• The satisfaction with quality of life
• The score on the depression Scale (CES-D Scale)
• The score on the perceived Stress Scale (PSS)

We consider now the households of the city of Torreón as they were not proposed the Piso Firme program and we define two groups: those who installed cement floors and those who didn't. But before going further, let's check the mean income of the two groups.

It looks like people who installed cement floors in their households have higher incomes. Such an observation was expected as households with greater incomes are more likley to spend money oon their housing. This is bad news as it could bias the results. To solve this problem, the considered households will be balanced using a matching algorithm on the income per capita of households. This way, samples with similar incomes will be considered ! Below you can find the mean income per capita in the two groups after matching.

Groups are balanced now. We can perform the regression analysis. Let's look how the installation of cement floors impact the happiness/satisfaction variables !

Now we perform a linear regression to observe how the installation of cement floors impact the happiness and satisfaction of households caretakers. Control variables (demographic, health, social and benefits from other social programs) are added to the model to mitigate their effects on the mental health indicators. The results are available below.

The first thing to notice is the lack of significance of most of the results (in grey in the figure above). The figure above shows that the installation of cement floors does improve floor satisfaction of about 11%, but there is no strong evidence saying it increases the house and life satisfaction significantly in other variables. It seems like we can not answer more accurately to this question with the used data set. Furthermore, the stress level doesn't seem to get lower, maybe because households need to spend a part of their revenues for it, creating potential economic concerns in those households. To increase happiness, advising households to invest in cement floors is not sufficient, governmental programs such as Piso Firme seem to be necessary for the well-being of these households.

But the budget of such programs are limited. Therefore in the next research question, we will search how to make the program more cost-efficient with the objective to make it available to a maximum number of households. One way to make Piso Firme less costly is to install less cement. In other words, we will try to propose less cement in households, but in a more efficient way !

To answer to this question, we are going to measure the effect of installation of cement floors on mental health in 4 different rooms :

• The bedroom
• The kitchen
• The dining room
• The bathroom

The considered mental health indicators will be the same as the ones previously cited. In order to assess the different impacts that each room has when getting a cement floor, a regression analysis is going to be performed. Our control group will be those households in which no cement floor has been installed.

The objective of these regressions is to determine in what rooms cement floors have the greatest benefits on the happiness indicators. This way installing cement floors in these rooms can be prioritized, and save money so that the government can reach more percentage of the population. Furthermore, a correction in each model is again performed to make sure the effects of other control variables (demographic, health, social and benefits from other social programs) do not change the results.

The figure above shows the effect that these 4 different rooms have on happiness indicators when cement floors are installed. All the results (with exception of Cement floors in bathrooms for perceived stress), are strongly significant. Even if all rooms have a positive influence on the happiness indicators, these can be prioritized in order to reduce the overall costs of the program, in such a way that more people can benefit from it, while optimizing the overall happiness indicators.

The room that has the top priority is the dining room, since it is, by almost all the indicators (with exception of the Perceived Stress), the one with the best performance, followed by the kitchen and the bedroom. The bathroom has the last place in the ranking.

What about other house improvements besides the installation of cement floors in different rooms ? What if other housing improvements such as restauration of walls or ceiling had greater benefits ? In order to assess that, we perform another regression analysis on the following variables for all the happiness indicators:

To answer to this question we perform another regression analysis on the following variables for all the happiness indicators:

• Installation of cement floor
• Construction of sanitary facilities
• Restoration of sanitary facilities
• Construction of ceiling
• The Restoration of walls

As can be seen in the figure, the only variable that has a significant impact on any happiness indicator is the installation of cement floors, on the “satisfaction with floor” indicator (no surprises there). All the other results have either negligible effect, or are not significant.

Thus, there is not enough evidence that the construction or restoration of sanitary facilities, construction of the ceiling, or restoration of walls have an impact on the happiness indicators

We found a significant increase of 11% in the satisfaction of floor quality in the households who invested in cement floors. But no significant result was found concerning the impact of investment in cement floors for households on the satisfaction with house quality, quality of life, depression and perceived stress. More data would need to be collected to find more. But even though satisfaction with the quality of floor increases significantly, the government should focus on providing financial aids such as Piso Firme to households as they showed stronger and more significant results. Furthermore, the households who need improvement of their quality of life the most are the ones who cannot afford an installation of cement floors.

Also, if we can rank the benefits that each house improvement has on the happiness of the mother or caretaker, we can propose a scenario for the government that can optimize the cost of the program, thus making it reach more people. We can see that this is indeed possible as the installation of cement floors in the dining room is the most impactful, followed closely by the cement floor in the kitchen and the cement floor in the bedroom, the bathroom comes only last.

Finally, we couldn't find significant results concerning the influence of all other housing improvements. But except the installation of cement floors, housing improvements have little to null effect on the happiness variables, thus, they can be put last in the priority for social programs conducted by the government. More data would need collected to perform a deeper study of the effect of different housing improvements on the mental health of caretakers in households.