Understanding Poverty: Absolute vs. Relative and Measurement Methods

Poverty is a word we hear constantly, but its meaning can feel elusive and complex. Is poverty simply about not having enough money for food, or does it include being unable to afford a standard life enjoyed by others in your society? The answer, as economists and policymakers in India and around the world have found, is that it’s both. Understanding the two main concepts-absolute and relative poverty-along with the sophisticated ways we measure them, is crucial to tackling this deeply ingrained economic challenge.

Two sides of the coin: absolute vs. relative poverty 🔗

When you hear about people living on less than a few dollars a day, you’re looking at a measure of absolute poverty. When you notice that some children in your city don’t have access to computers for school projects, while their peers do, that touches upon relative poverty. These two frameworks help define the threshold of deprivation.

Absolute poverty: a minimum survival standard 🔗

Absolute poverty is the most straightforward, focusing on the minimum essentials needed for physical survival. A person is deemed absolutely poor if their income or consumption expenditure is insufficient to meet their basic human needs, such as food, safe drinking water, clothing, shelter, and basic healthcare. This threshold is generally fixed over time, regardless of the country’s economic growth. It represents a severe level of deprivation that threatens basic human existence.

Think of it like a fixed, non-negotiable floor of survival. If a family in rural India cannot afford the minimum required calories or a basic roof over their heads, they are experiencing absolute poverty.

Relative poverty: income inequality and social exclusion 🔗

Relative poverty, in contrast, is defined in relation to the prevailing income distribution and living standards within a specific society or country. It’s not about mere survival but about social inclusion and inequality. For instance, in a high-income nation, a person may be able to afford food and shelter but is considered relatively poor if their income is less than 50% or 60% of the median household income. They might be unable to afford a car, internet access, or the occasional movie-things that are considered a typical part of life in that society.

Unlike the fixed floor of absolute poverty, the relative poverty line rises as a society’s overall wealth increases. A person in relative poverty in Mumbai might be considered rich by the standards of a remote village in Africa. This concept is critical for understanding the social exclusion and economic disparity that exist even in prosperous societies.

The poverty line in india: an evolving measure 🔗

The definition and measurement of the Poverty Line in India have been a subject of intense debate and evolution for decades. Since the initial estimates by Dadabhai Naoroji, the methodology has continually shifted to capture the true cost of a decent life, moving beyond a simple calorie count.

From calories to consumption expenditure 🔗

Historically, India’s poverty line was anchored to a simple nutritional norm-the cost of buying a minimum daily calorie intake (e.g., 2,400 kcal in rural areas and 2,100 kcal in urban areas). While simple, this approach was criticized for ignoring essential non-food expenses.

The Tendulkar committee methodology 🔗

The Expert Group led by Suresh Tendulkar (2009) marked a significant methodological shift. The Tendulkar Committee abandoned the exclusive reliance on the calorie norm and moved towards a uniform poverty line basket (PLB) for both rural and urban areas. Crucially, it factored in private expenditure on health and education, alongside food and other essential non-food items, making the poverty line more realistic and comprehensive than previous models.

The rangarajan committee’s push for a higher bar 🔗

The C. Rangarajan Committee (2014), constituted to review the methodology, sought to raise the bar further. It reverted to the practice of having separate all-India rural and urban poverty line baskets and adopted a more nuanced approach. The Rangarajan methodology included:

1. A normative level of adequate nutrition.
2. Behaviourally determined expenditure on essential non-food items (like clothing, housing).
3. A provision for a margin of non-food expenses for transport and savings capacity.

This approach led to higher poverty lines (e.g., &₹;1,407 per person per month for urban areas in 2011-12) than the Tendulkar estimates, reflecting a more expensive and comprehensive basket of goods and services considered essential for a minimum standard of living. Though not officially adopted, its principles continue to influence ongoing policy discussions.

The continuous revision of the poverty line, though often controversial, underscores the recognition by bodies like NITI Aayog that poverty is not just a monetary issue but a multidimensional one.

Beyond the count: measuring the depth of poverty 🔗

Counting the number of poor people is the first step, but not all poor are equally poor. Economists use sophisticated indices to measure not just the incidence of poverty, but also its depth and severity. These measures are part of the Foster-Greer-Thorbecke (FGT) family of poverty indices.

The headcount ratio (P0) method 🔗

The simplest and most widely used measure is the Headcount Ratio ($P_0$). It is calculated as the proportion of the population whose income or consumption falls below the poverty line:

$$P_0 = \frac{N_p}{N}$$

Where $N_p$ is the number of poor people and $N$ is the total population.

Strengths and weaknesses:

• Strength: It is simple to understand, easy to calculate, and provides a clear picture of the prevalence of poverty. For example, a headcount ratio of 20% means one in five people are poor.
• Weakness: Its major flaw is that it ignores the depth of poverty. If a person just below the poverty line gets a little richer, but stays poor, the index is unchanged. More critically, if the poorest of the poor get even poorer, the headcount ratio also remains unchanged. It is insensitive to the distribution of income among the poor.

The poverty gap ratio (P1) method 🔗

To overcome the limitations of the Headcount Ratio, economists use the Poverty Gap Ratio ($P_1$). This ratio provides a measure of the depth of poverty. It calculates the average shortfall of the income of all poor individuals from the poverty line, expressed as a percentage of the poverty line.

Conceptually, it tells us the total amount of money required to bring every poor person exactly up to the poverty line, assuming perfectly targeted transfers. The formula is:

$$P_1 = \frac{1}{N} \sum_{i=1}^{N} \left(\frac{Z – Y_i}{Z}\right) \cdot I_i$$

Where $Z$ is the poverty line, $Y_i$ is the income of the $i$-th individual, and $I_i$ is an indicator function that equals 1 if the individual is poor (i.e., $Y_i < Z$) and 0 otherwise. This is effectively the average poverty gap divided by the poverty line.

Significance:

The Poverty Gap Ratio is superior to the Headcount Ratio because it reflects the intensity of deprivation. If the poor become poorer (moving further away from the poverty line), the Poverty Gap Ratio will increase, signaling a more severe problem. It helps governments determine the total resource allocation required for poverty alleviation programs.

The squared poverty gap ratio (P2) method 🔗

While the Poverty Gap Ratio captures the depth of poverty, it still has a limitation: it treats a shortfall of ₹100 from the poverty line the same for a person who is ₹1,000 below the line and a person who is ₹10,000 below. It doesn’t account for inequality among the poor.

The Squared Poverty Gap Ratio ($P_2$) addresses this by squaring the proportionate poverty gaps. The formula is:

$$P_2 = \frac{1}{N} \sum_{i=1}^{N} \left(\frac{Z – Y_i}{Z}\right)^2 \cdot I_i$$

The weighting effect:

By squaring the gap, the measure places a disproportionately higher weight on the income shortfalls of the poorest individuals. For example, doubling a person’s income gap from 10% to 20% of the poverty line doesn’t just double their contribution to the index; it quadruples it (because $0.2^2$ is four times $0.1^2$).

This means the $P_2$ measure is highly sensitive to the severity of poverty and the distribution of income among the poor. A policy that benefits the poorest of the poor the most will result in the largest reduction in the Squared Poverty Gap Ratio, making it a powerful tool for targeting the most vulnerable.

Conclusion: the multi-layered challenge 🔗

Poverty, whether absolute or relative, remains a central challenge for a developing economy like India. The shift in poverty measurement from rudimentary calorie counts to the comprehensive consumption-based poverty line and, more recently, to the Multidimensional Poverty Index (MPI) by NITI Aayog reflects a continuous effort to capture its complexity. By employing nuanced metrics like the Headcount, Poverty Gap, and Squared Poverty Gap ratios, policymakers gain better insight into not just who is poor, but how poor they are, allowing for the design of more effective, targeted, and equitable poverty alleviation strategies.

What do you think? Given that the simplest measure, the Headcount Ratio, is often the most publicly reported, what are the potential policy-making implications of ignoring the “depth of poverty” as measured by the Poverty Gap Ratio? Should the official poverty line in India be based purely on absolute needs for survival, or should it incorporate a component of relative needs to address growing social inequality?

References

1. https://www.ebsco.com/research-starters/social-sciences-and-humanities/absolute-and-relative-poverty
2. https://vajiramandravi.com/current-affairs/differences-between-absolute-poverty-and-relative-poverty/
3. https://www.drishtiias.com/to-the-points/paper3/poverty-estimation-in-india
4. https://ekamiasacademy.in/rangarajan-poverty-line/
5. https://www.pib.gov.in/PressReleaseIframePage.aspx?PRID=1996271
6. https://www.investopedia.com/terms/p/poverty-gap.asp
7. https://www.ilo.org/sites/default/files/wcmsp5/groups/public/@americas/@ro-lima/@sro-port_of_spain/documents/presentation/wcms_304851.pdf
8. https://www.niti.gov.in/sites/default/files/2021-11/National_MPI_India-11242021.pdf