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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>M. Cremaschi);</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Poverty in Elderly</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Stefania Bandini</string-name>
          <email>stefania.bandini@unimib.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Valeria Marina Borodi</string-name>
          <email>valeria.borodi@unimib.it</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>David Chieregato</string-name>
          <email>david.chieregato@unimib.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marco Cremaschi</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Federica D'Antico</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vincenzina Messina</string-name>
          <email>enza.messina@unimib.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marco Terraneo</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Laura Terzera</string-name>
          <email>laura.terzera@unimib.it</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Francesca Gasparini</string-name>
          <email>francesca.gasparini@unimib.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="editor">
          <string-name>Multidimensional Poverty, Elderly, Bayesian Network, Sustainability,</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Computer Science</institution>
          ,
          <addr-line>Systems and Communications</addr-line>
          ,
          <institution>University of Milano - Bicocca</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Sociology and Social Research, University of Milano - Bicocca</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Department of Statistics and Quantitative Methods, University of Milano - Bicocca</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2021</year>
      </pub-date>
      <volume>000</volume>
      <fpage>0</fpage>
      <lpage>0002</lpage>
      <abstract>
        <p>Poverty is a multidimensional concept that, besides the economic status and financial resources, should consider the lack of access to resources enabling a minimum standard of living and participation in society. In particular, elderly people are likely to require help with some or everyday activities and the total costs of this help can be very high and absorb a significant amount of their income, especially when they are alone and not in good health. This work proposes a strategy based on Bayesian Network to identify the risk of poverty in elderly people, relying on multidimensional indicators learned from heterogeneous sources of information, including the dificulty of accessing services, social exclusion and health status. Data cleaning and integration that include socio-demographic indicators are proposed here, and an overall framework of analysis that can be exportable to several other categories of the population at risk of poverty is presented.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Poverty is one of the most significant social problems in Organization for Economic Cooperation
and Development (OECD) countries. The focus on financial resources alone does not capture
people’s quality of life as being poor means a lack of access to resources enabling a minimum
nEvelop-O
standard of living and participation in societies: thus, a multidimensional approach is needed.
Socio-economic vulnerability is accompanied by social networks impoverishment [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], and those
in low socio-economic status have less chance of obtaining social support, e.g., in terms of
needed care [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. This work considers a well-defined group of persons facing poverty – the
elderly.
      </p>
      <p>Starting from these observations, in this work, we consider data not only on income and wealth
but also on material and social deprivation that are rarely collected or known by public welfare
institutions, making it dificult to intercept those who require more support. The material
deprivation captures the ability of individuals and households to aford specific types of goods
and services. In contrast, social deprivation refers to a systematic exclusion of individuals,
families and groups from participation in economic, political and social activities. This work
proposes to include the dificulty of accessing services, social exclusion and health status while
evaluating the risk of poverty. Moreover, it aims to investigate also how the co-presence of
these conditions could even worsen susceptibility to poverty. This work starts by analysing a
dataset on the elderly in Lombardy, which records their major needs, requests for assistance,
and information about their social network before and during the COVID-19 pandemic. These
data are cross-linked and integrated with other existing relevant data (such as the open access
data from the selected municipalities, statistics, economic and health status conditions) and will
be complemented with new data collected through dedicated questionnaires administered to
the elderly to capture new indicators useful to predict the risk of poverty. The final aim of our
proposal is to categorise the elderly risk of poverty by using the metaphor of an alert semaphore
(“ampel” in German) as red, yellow and green code, i.e., major, moderate and low or zero risk,
thus providing a quick and exploitable prioritisation outcome, that can be exploited by welfare
policy makers for poverty eradication and health promotion, especially to guide actions in case
of emergencies, such as COVID-19 pandemic.</p>
      <p>To this end, we propose a strategy based on Bayesian Networks (BNs) to exploit their ability to
model dependency relationships among the variables. BNs are a probabilistic graphical model
for representing knowledge about an uncertain domain where each node corresponds to a
random variable, and each edge represents the conditional probability for the corresponding
random variables [3]. One of the positive aspects of the BNs is the possibility to easily include
prior background knowledge from the experts.</p>
      <p>The paper is organised as follows. In Section 2, a brief state-of-the-art on multidimensional
poverty and machine learning approaches to face this problem, especially in the case of the
elderly, is reported. In Section 3 the data and source of data considered are presented. In
Section 4, the proposed framework of analysis is described, and the adopted preprocessing on
the considered data is reported in Section 5. In Section 6 the proposed implementation of the
BN is reported, together with the preliminary results obtained. Finally, we conclude this paper
and discuss the future direction in Section 7.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Background</title>
      <p>Populations in OECD countries are ageing rapidly, their health worsens, and they may struggle
with everyday activities. As World Health Organization (WHO) states, Long-Term Care (LTC)
systems enable people experiencing significant declines in capacity to receive care consistent
with their basic needs. LTC services help reduce the inappropriate use of acute healthcare
services, help families avoid catastrophic care expenditures and free women – usually the main
caregivers – to have broader social roles [4]. Incomes of the elderly are generally low: 23%
of older people are likely to be at risk of relative income poverty, the same figure being 18%
in the overall population, and this phenomenon interests 25 out of 35 OECD countries [5].
The financial challenges faced by older people with LTC needs can be very high and absorb
a significant amount of their income. Home care and small out-of-pocket payments may be
unafordable without adequate social protection. LTC needs are relevant indicators to address
from a multidimensional perspective, especially among the elderly. Women are more likely to
be in poor conditions and, thus, at risk of socioeconomic disadvantage [6], the reasons being
lower female participation in the labour market (working fewer hours and with lower salaries);
moreover, women have primary responsibility for childbirth, child rearing and unpaid domestic
work [7]. These factors place women at a disadvantage in a pension system that is tied to
labour market earnings. All the factors associated with being female such as low income, being
widowed, higher life expectancy than men and older age, are associated with requiring LTC
[8].</p>
      <p>Most studies emphasize the economic facet of poverty on the basis of monetary income [9, 10, 11].
However, income-based indicators are poor proxies of material conditions among the elderly
[12, 13] whereas non-monetary ones improve our understanding of who is poor, with a shift
from a unidimensional to a multidimensional approach [14],[15].</p>
      <p>In 2010 the Multidimensional Poverty Index (MPI), was oficially published by Oxford Poverty
and Human Development Initiative1 in collaboration with Human Development Report Ofice
of the United Nations Development Programme (UNDP) [16]. The MPI Indicator is the first
attempt to represent the multidimensional poverty. It considers poverty through ten indicators
divided into three dimensions: health, education and standard of living. The dimensions are
equally weighted, and so are the specific indicators. Later, in 2015 2, they come to the MPI side
by side:
1. the concept of measuring well-being made up of eleven specific dimensions;
2. the concept of social cohesion, consisting of measures concerning inclusion, capital and
social mobility;
3. the Social Institutions and Gender Index (SIGI), concerning discrimination factors.
Multidimensional measures of deprivation are composed of diferent indicators fitting into a
synthetic scale [17, 18], which is deemed to reflect basic living standards and the exclusion
from the minimum acceptable way of life in one’s own society. Several methodologies to assess
1ophi.org.uk
2www.oecd.org/dac/post-2015.htm
poverty from a multidimensional perspective exist, including methods aiming to implement
aggregate data from diferent sources, and statistical approaches – i.e., principal component
analysis, or cluster analysis – which reflect the joint distribution of single deprivation indicators
and aim to a bottom-up definition of synthetic scales [ 19]. Such approaches are adequate if
they capture the joint distribution of deprivations, identify the poor ones (i.e., dichotomising
the population into poor and non-poor), and provide a single cardinal figure to assess poverty.
Although there is little research on Machine Learning (ML) and Artificial intelligence ( AI)
application to poverty estimation, thanks to recent advances in data obtainability, big data and
ML are nowadays adopted to predict poverty in low-income countries. Besides the choice of
the best algorithms, other crucial aspects, such as data quality and the presence of bias due
to subjective and indirectly related data, exist, pushing to choosing other data sources such
as remote sensing datasets [20]. A second issue is related to the dificulties in finding labelled
data. Ensemble models were employed, assuming as ground truth for ML training the Proxy
Means Test (PMT) labels, without verifying the accuracy of the PMT labels [21]. Finally, in the
presence of a noisy dataset, it is crucial to select robust features to feed ML algorithms and to
understand how these features can contribute to the identification of poverty clusters, which
is not obvious when using complex heterogeneous data. Among diferent ML techniques for
poverty classification, decision tree [ 22], random forest [21], and ensemble approaches [23] are
the most used.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Datasets description</title>
      <p>This work relies on four diferent datasets to acquire multidimensional indicators of poverty in
the case of the elderly and to detect the mutual correlation among them.</p>
      <p>1. AD (AUSER Dataset): this is an unconventional and valuable dataset collected by AUSER3,
an Italian association that promotes active ageing. These data have been collected by
volunteers in nine municipalities in the Lombardy region, which records the major
needs of the elderly, requests for assistance, and information about their social network,
both before and during the COVID-19 pandemic (years 2019, 2020, and 2021). The nine
municipalities and the elderly that refer to them are reported in Figure 1.
2. CD (Context Data): Demographic and socio-economic retrospective data, collected from
public open data, that enable socio-demographic comparisons of groups of citizens in
diferent municipalities.
3. RD: Retrospective Data on health, disability and ageing, collected during concluded
projects, TAPAS [24] and IDAGIT [25], on a similar population of elderly in Lombardy,
that enables addressing the impact of health, disability and comorbidity on wealth and
vice-versa.
4. ND (New Data): for a selected representative sample of the elderly, ad-hoc surveys are
administered through a structured questionnaire to acquire information on elderly social
deprivation, their health and well-being.</p>
    </sec>
    <sec id="sec-4">
      <title>4. The proposed framework of analysis</title>
      <p>The framework of analysis presented here has two main objectives:
• identifications of novel indicators of poverty risk and of their mutual interference based
on longitudinal data that grasp information from daily dificulties and that could reveal
new social criticalities that social services, municipalities and other public institutions
will have to face;
• definition of an AI model that, managing heterogeneous data, will provide a poverty risk
prediction, simplified in a three-level semaphore alert: red (high), yellow (medium) and
green (low or absent) risk. Besides the human and social benefits, it is noteworthy that
such a prioritisation will allow a high-level organisation of the management bodies to
care for people with vital long-term care needs, which will result in a significant impact
on poverty.</p>
      <p>In this work, a Bayesian Network (BN) model is proposed to define diferent levels of risk of
poverty. We start considering the AD dataset, which can be considered a novel, unconventional
and valid data source. This dataset requires essential preliminary steps of data preprocessing to
clean and normalise the data entries and to be enriched with the collected Context Data (CD).
Starting from these two merged datasets, we create the Enriched Dataset (ED), where each
record corresponds to one elderly person and all the related information.</p>
      <p>Starting from the ED dataset, the framework will be applied in three incremental steps of detail:
i) we decide to adopt the Gini Index[26] as initial target of the BN. This index represents the
income inequality, and not directly a multidimensional deprivation index, which is our focus,
however it shares common ground with poverty indexes, permitting, while we are collecting
new data, a first validation of the proposed framework; ii) the data from RD TAPAS and IDAGIT
is integrated, and the expert’s domain knowledge is consolidated into the model; iii) the data
collected from additional questionnaires provided by AUSER can be used as groundthruth for
ifnal model validation. The collection of this data is still ongoing.</p>
      <sec id="sec-4-1">
        <title>The present paper describes the first step among the three listed.</title>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Data preprocessing</title>
      <p>The AD dataset results from the interaction of the nine AUSER municipalities and the elderly
that refer to them through the phone service Filo D’Argento. Specifically, the data provided
by each municipality are contained in a spreadsheet where each row represents an interaction
with a beneficiary. Each interaction, which can be a simple request for information or a
service request, is characterised by data concerning the beneficiary, details about the service
or information requested and specific data on the call. For reasons related to privacy, the
beneficiary is represented by an identification code that replaces their name and surname. The
data concerning them include non-specific physical or economic locations and characteristics.
In detail, the most relevant data are the municipality of residence, date of birth, if there are
contact persons, if the beneficiary lives alone, and if he is self-suficient or retired. As for
services, the data are more specific: there are all the possible details regarding the type, timing,
places and any service problems. The entire dataset is characterised by a low quality of the
data in terms of correctness and completeness, as they are the result of the manual entry of the
volunteers and therefore contain numerous typos and missing data. Focusing solely on the data
concerning the over 65s, we obtained a dataset composed of 52.939 services relating to 3.493
beneficiaries with a percentage of missing data of about 15% (1 958 743 data of which 298 500 are
missing). For this reason, a cleanup and normalisation phase has been inserted in the pipeline
described in Section 5.1. A sample of the AD dataset can be found in the Table 2.
To make the dataset more suitable for the application of the ML algorithm, we defined a
pipeline consisting of three phases: i) Data cleaning and Normalisation; ii) Enrichment; and iii)
Training.</p>
      <sec id="sec-5-1">
        <title>5.1. Cleaning and Normalisation</title>
        <p>
          In the data cleaning and normalisation phase, firstly, textual data are converted to integers. In
detail, groups of values have been identified and each of them have been associated with a
number (e.g., sex: [M,F] →[
          <xref ref-type="bibr" rid="ref1 ref2">1,2</xref>
          ], Privacy Consent: [yes,no,missing] →[
          <xref ref-type="bibr" rid="ref1 ref2">1,2,99</xref>
          ]). The ID of the
beneficiary (Beneficiary ID), the city of birth and residence, date and time of the
service/information request have been excluded from the processed columns. In order to ease any possible
additional data integration, the places of birth and residence ISTAT4 codes, together with age,
year of service and municipality where the data comes from, are stored in every line.
        </p>
        <p>4Italian national statistics ofice.</p>
        <p>Going more in-depth with the cleaning procedure, the next steps are:
1. Removal of duplicate columns;
2. Removal of accents and apostrophes (e.g., Cantù →Cantu; CANTU'→CANTU);
3. Convert text to lowercase (e.g., Cantu →cantu; CANTU →cantu);
4. Edit column headings - no spaces, lowercase initials and typo fix ( e.g., year of birth
→rptYearOfBirth; rptRet1red →rptRetired; “Year ” →“Year”)
5. There are two diferent columns representing a singular boolean value; this data is
transformed into a single column: the new column stores the 0 value for service requests
and 1 value for information requests;
6. Missing information for some columns can be determined by the text present in the note
column, (i.e., strings “partially self-suficient”, “wheelchair”, “disabled”, “guest”, “lives
alone” can resolve the column rptSelfsuficiency);
7. The columns that are not needed after this step are dropped ( e.g., ‘rptNote’);
8. Numeric columns wrongly identified as strings are converted to float, and other minor
transformations are applied to ensure correct column classification.</p>
        <p>A small subset example of the AD dataset after the cleaning and normalisation phase is shown
in Table 3.</p>
      </sec>
      <sec id="sec-5-2">
        <title>5.2. Enrichment</title>
        <p>As soon as the original dataset AD is ready for ML algorithms, it can be enriched with new
data (resulting in the ADE dataset). A first analysis brought us to the requirement to integrate
also the province from the residency because some of the public data is available only on the
province level and not on the municipality level. The integrated data include several areas such
as mobility, health and job statistics.</p>
        <p>Urban Index5, in Italy, there is a public portal with indicators for Urban Policies distributed as
OpenData6. However, most of those indicators are pretty old, there are potentially valuable
data in the dataset. More in detail, the Gini index7 is a measure of statistical dispersion intended
to represent income inequality or wealth inequality within a nation or a social group. This
5www.urbanindex.it
6www.urbanindex.it/opendata/DB_DIPE.zip
7www.urbanindex.it/indicatori/indice-di-gini
index was used as the first target example as a poverty measure and was integrated into the
original dataset by the municipality of residence.</p>
        <p>Open Data Lombardia8, provides data related to indicators about population health and
healthcare. Among these, it was decided to integrate:
• RSA (Nursing Home Residence) rate, the ratio between the number of beds in the nursing
homes and the number of inhabitants over 65 per thousand;
• Rate of social ofers for the elderly (sheltered accommodation and day centres), the ratio
between the number of beds in social ofers for the elderly and the number of inhabitants
over 65 per thousand;
• Rate of social cooperatives for the elderly, ratio between the number of social cooperatives
for the elderly and the number of inhabitants over 65 per 100 thousand.</p>
        <p>All the rates listed above have been integrated through the municipality of residence.
Istat9, instead, makes the information on demographic indicators accessible, those selected for
integration were:
• Ageing index, rate between the number of inhabitants over 65 and the number of young
people up to 14 years old per cent.</p>
        <p>Integrated through the municipality of residence and year.
• Turnover rate of the active population, rate between the population aged 60-64 and the
population aged 15-19 per cent.</p>
        <p>Integrated through the municipality of residence and year.
• Masculinity index (complementary to the femininity index), rate between males over 65
and females over 65 per cent.</p>
        <p>Integrated through the municipality of residence and year.
• Retirment rate of over 65s, rate between the number of retirees over 65 and the population
over 65 per thousand.</p>
        <p>Integrated through the province of residence and year.
• Elderly dependency index, rate between the population over 65 and the population aged
15-64 per cent.</p>
        <p>Integrated through the municipality of residence and year.
• Mortality rate.</p>
        <p>Integrated through the municipality of residence, year, gender and age of the beneficiary.</p>
        <sec id="sec-5-2-1">
          <title>A sample for the ADE dataset is available in Table 4.</title>
        </sec>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Bayesian Network</title>
      <p>As for the prediction aspects of an individual’s poverty index, Bayesian Networks have been
chosen as they are self-explainable; namely, they allow to know which variables led to a
8dati.lombardia.it
9www.istat.it
specific result and to what extent each single data contributed to the final result. Regarding the
implementation, there is a wrapper class which allows the configuration of the parameters of
the pyAgrum10 library. This library has been selected among the many available (e.g., Pgmpy,
bnlearn, sklearn, Pythin, pomegranate, PyBNesian) for the remarkable possibilities of rapid
prototyping and production of charts.</p>
      <p>Recalling that we have not yet the final data of the ongoing data collection that will provide the
groundtruth label in terms of poverty, we decided to adopt the Gini Index as the target to analyse
the feasibility of the proposed framework. Even if this index represents only income inequality
and does not consider multidimensional variables of deprivation, it shares common ground
with poverty indexes, permitting a first validation of the proposed Bayesian Network.
To obtain a preliminary version of our model, the ED dataset has been used. The training is
carried out using 80% of the data, while the remainder is used as a test set. This data split has
been performed randomly. Using the Gini index as target index, the BN automatically identifies
4 classes. The pipeline was developed with a Python Jupyther Notebook instance. The data
cannot be shared due to privacy and GDPR concerns. In Table 5 available statistics about the
dataset are reported.
Background knowledge integration The manual addition of arcs (called ’mandatory_arcs’)
allows the integration of the initial data with the domain knowledge acquired from the literature
or directly from experts. In the same way, it is possible to remove arcs with the ’tabu_arc’ list
to avoid incidental correlations. In Figure 1 the initial BN is reported. In Figure 2 instead, we
can see the correlation between representative variables of the initial model. It is possible to
notice that the link between column “rptAnnoNascita” (birthYear) and the target Gini index is
an incidental strict correlation because there is no demonstrated reason to say that older people
are poorer even if the data of this dataset may suggest so. For this reason, we can identify this
as a ’tabu_arc’. As a representative example of integration of knowledge from domain experts,
it was established to force the arch between the rate of available beds (RSA rate) with the target
Gini Index.</p>
      <p>In Figure 3 it’s possible to see the BN with a first attempt to integrate domain knowledge. At
the same time Figure 4 shows the updated inference diagram.</p>
      <p>The model described in this section will be further improved with the RD dataset and will be
completed and optimised once the ND dataset is available.</p>
      <sec id="sec-6-1">
        <title>6.1. Validation</title>
        <p>The validation was executed against the ED dataset, which was divided as described above (the
20% of the 3493 beneficiaries have been selected as a test set). For the Gini Index, the Bayesian
Network automatically identifies 4 classes as the target, so this experiment is carried on with
this aggregated index with 4 classes. The results of our experiment show a performance of 0.49
of accuracy with a weighted f1-score of 0.46 (accuracy of the random baseline is 0.25). Since
data acquisition is still ongoing, and we have not yet fully integrated the domain knowledge,
these preliminary results can be considered promising. As described in Section 1, we plan to
use a three-level semaphore classifier as the target in the future, integrating further data.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Conclusion and future work</title>
      <p>In this paper, we present a framework to analyse unconventional and heterogeneous data to
define a three-level risk of poverty index for elderly people and, at the same time, identify novel
indicators of multidimensional poverty. A Bayesian Network approach is proposed to encode
background and domain expert information and underline mutual interference among all the
considered variables. Further subsequent tests are planned to identify any under-represented
variables. Preliminary results, validated with a state-of-the-art inequality index, confirm the
power of the proposed solution. In the future, knowledge from the analysis of already concluded
projects and ongoing questionnaire collection will be integrated into the model to answer the
research questions better.</p>
    </sec>
    <sec id="sec-8">
      <title>Acknowledgments</title>
      <p>This research is supported by the FONDAZIONE CARIPLO “AMPEL: Artificial intelligence
facing Multidimensional Poverty in ELderly” (Ref. 2020-0232).
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