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Trang 1Journal of Southeast Asian Economies Vol 31, No 1 (2014), pp 103–19 ISSN 2339-5095 print / ISSN 2339-5206 electronic
DOI: 10.1355/ae31-1g
OTHER ARTICLES
Impact of Household Credit on Education and Healthcare Spending
by the Poor in Peri-Urban Areas,
Vietnam Tinh Doan, John Gibson and Mark Holmes
There is an ongoing debate about whether microfinance has a positive impact on education and health for borrowing households in developing countries To understand this debate,
we use a survey designed to meet the conditions for propensity score matching (PSM) and examine the impact of household credit on education and healthcare spending by the poor
in peri-urban areas of Ho Chi Minh City, Vietnam In addition to matching statistically identical non-borrowers to borrowers, our estimates also control for household pre-treatment income and assets, which may be associated with unobservable factors affecting both credit participation and the outcomes of interest The PSM estimates show a significant and positive impact of borrowing on education and healthcare spending However, further investigation of the effects of the treatment reveals that only formal credit has a significant and positive impact
on education and healthcare spending, while informal credit has an insignificant impact on spending This paper contributes to the limited literature on peri-urban areas using evidence from one of the largest and most dynamic cities in Southeast Asia.
Keywords: Matching, education and healthcare spending, household credit, the poor, peri-urban.
I Introduction
Microfinance has increasingly attracted attention
from the global development community because
it is considered a powerful tool for alleviating
poverty in developing countries An argument commonly made in support of microfinance is that
it may help keep household production stable and mitigate adverse shocks, thus preventing school
Trang 2(Armendariz and Morduch 2010; Dehejia and
Gatti 2002; Edmonds, 2006; Jacoby and Skoufias
1997; Maldonado and Gonzalez-Vega 2008)
Education and health are critical to sustainable
poverty reduction since they affect the formation
of quality human capital and the productivity of
future generations
There is ongoing debate about the impact of
microfinance (Cull, Kunt and Morduch 2009) on
borrowing households’ access to education and
healthcare On the one hand, microcredit has
a positive impact on education; girls received
more schooling if households borrowed from the
Grameen Bank (Pitt and Khandker 1998) On
the other hand, some studies find no effects or
adverse effects on children’s education (Hazarika
and Sarangi 2008; Islam and Choe 2009; Morduch
1998) Likewise, in terms of health, Pitt et al
(2003) find higher weight-for-age and
height-for-age levels amongst children of Grameen Bank
borrowers, but Coleman (2006) observes a negative
impact of microcredit on healthcare spending by
households in northeast Thailand These differing
outcomes are discussed in greater detail in the
literature review (section II)
One difficulty in evaluating the impact of
microcredit is that borrowing and non-borrowing
households typically differ in both observable
and unobservable characteristics Borrowers may
self-select into borrowing activities due to their
“better” characteristics, thus making it challenging
to form a counterfactual of what would have
happened to borrowers in the absence of credit
If studies fail to correct for this problem of self-selection, the estimates will be nạve and overstated
(Coleman 2006) The propensity score matching
(PSM) method may help avoid this problem In
this approach, the effects of the treatment (i.e.,
borrowing/credit participation) are estimated
by simulating a randomized experiment with a
treatment and control group Households in the
treatment group are matched, based on observable
characteristics/factors, to other similar households
that will then form the control group It is assumed
that the matched households in the control group
would have no systematic differences in response to
the treatment, thus offering a valid counterfactual
When used appropriately, PSM can replicate the advantages of a randomized experiment (Dehejia and Wahba 2002)
In this paper, a survey, designed by the authors
to meet the conditions under which PSM works well, is used to examine the impact of household credit on education and healthcare spending by the poor in the peri-urban areas of Ho Chi Minh City (HCMC), Vietnam In addition to matching statistically identical non-borrowers to borrowers, our estimates also control for pre-treatment household income and assets These pre-treatment variables may be associated with unobservable factors affecting both credit participation and the outcomes of interest; therefore the inclusion of these variables helps reduce bias
Apart from the use of PSM, four other important features of the current analysis warrant comment
First, the analysis takes both formal and informal credit into consideration Most studies have examined the impact of formal or programme credit but have not considered the effects of credit from other sources (Coleman 2006; Khandker 2005; Morduch 1998; Pitt and Khandker 1998)
Our survey contributes to the exiting literature by capturing all sources of credit; the results reported below compare the effects of formal and informal credit (provided by relatives, friends, neighbours and informal moneylenders) Policy-makers often influence access to formal credit but have less leverage over informal credit; hence distinguishing their separate impact is of interest
Secondly, we provide evidence from a newly industrializing peri-urban area (District 9) in one of the largest and most dynamic Southeast Asian cities Our findings may therefore have external relevance for peri-urban areas in the rest
of Southeast Asia Peri-urban areas are defined
as places where industrialization has led to rapid urbanization and in-migration Rapid urbanization displaces poverty from rural to urban areas, resulting in the rapid urbanization of poverty In Vietnam’s urban areas, poverty levels have risen from 5.99 per cent in 1998 to 6.63 per cent in
2008 due to rapid population growth in these areas over the same period (VDR 2010)
Trang 3Thirdly, most non-experimental research designs
found in the existing literature on microcredit and
human capital lack valid counterfactuals of the
outcome for borrowers if they had not borrowed
Further, they typically make comparisons between
borrowers and non-borrowers without adopting
a plausible mechanism for dealing with
self-selection
Finally, although a comparison of the outcomes
for borrowers and non-borrowers using PSM is at
risk of being unreliable if the groups that are being
compared are too different, our empirical approach
minimizes the differences between the two groups
in order to enhance the validity of the PSM
approach (Dehejia and Wahba 2002) Therefore,
this paper also provides recommendations for
overcoming the potential weakness of the PSM
method
The rest of this paper is organized as follows:
Section II reviews the literature on household
credit and its impact on education and healthcare;
section III discusses the methodology employed;
empirical results are reported in section IV;
followed by concluding remarks in section V
II Literature Review
As was mentioned above, credit may affect
household demand for education and healthcare
in two ways (Armendariz and Morduch 2010)
Microcredit may help households earn higher
incomes, in turn, raising consumption and
increasing demand for healthcare and children’s
education In a contrasting example, if access to
credit raises female economic activity, children
may be taken out of school to replace maternal
input in the care of younger siblings or to work in
expanded household businesses
The evidence on these opposing effects of credit
participation is mixed Dehejia and Gatti (2002),
Edmonds (2006) and Jacoby and Skoufias (1997)
find that inadequate schooling in poor countries
can often be attributed to the lack of access to
credit — households facing adverse shocks may
pull children out of schools to reduce expenditure
and increase household income by increasing
children’s working hours Yet, in the same vein,
Hazarika and Sarangi (2008) find that borrowing households may take children out of school to work in family businesses Because small loans are often associated with higher interest rates and short-term repayment conditions, poor borrowers may reduce costs by using their own labour, which may include child labour, in order to accrue high returns for the repayment of loans and interest For example, a study on Vietnam finds that households that borrowed from lenders with higher interest rates used more child labour (Beegle, Dehejia and Gatti 2004)
There is also some interplay between healthcare and education If borrowing enables parents to promptly provide medication when children fall sick; children may recover faster and can stay in school Healthier children not only perform better
in school but are more likely to stay in school for longer such that they grow up to be more productive adults In contrast, low school achievement and attendance rates are associated with malnutrition (Glewwe, Jacoby and King 2000) It has been observed that microfinance clients consume healthcare services such as pasteurization, health insurance, family planning and pregnant-mother care more often than non-clients (CGAP 2003)
III Analytical Framework
III.1 Data
Four hundred and eleven borrowing and non-borrowing households were interviewed in early 2008 in the peri-urban District 9 (HCMC, Vietnam).1 Since our focus is on the impact of microcredit on poor households, our sample was selected from a list of households with an initial per capita income below the HCMC general poverty line of VND6 million (approximately US$1 per day).2 The sampling was carried out in two steps:
we first selected wards within District 9 and then selected households from those wards The target sample size was set at 500 households, including
100 reserves, to achieve a realized sample of
400 In fact, 411 households were successfully interviewed, accounting for 26 per cent of the total number of poor households in each of the selected
Trang 4wards in the district The sample comprises 304
borrowing households and 107 non-borrowing
households, with a total of 2,062 members: 955
(46.3 per cent) males and 1,102 (53.7 per cent)
females More information on the sources of credit
and the households’ per capita income prior to the
treatment (borrowing) can be found in Appendix 1
The survey was designed to collect data on
household-level and individual-level variables:
commune characteristics, household durable
and fixed assets, borrowing and expenditure on
healthcare, food and non-food items, and children’s
schooling and education We also utilized GPS
receivers to collect data on the location of the
households and to measure their distances from
facilities, such as schools
III.2 Challenges to Evaluating Impact
The main challenge to evaluating the impact of
credit is the difficulty of separating the causal
effect of credit from selection and reverse causation
biases, which are common to nearly all statistical
evaluations (Armendariz and Morduch 2010)
In order to separate the effects of the treatment
from other factors, we have to ask how borrowers
would have managed without credit (Armendariz
and Morduch 2010) This question is not easy to
answer because researchers are unable to observe
the virtual outcomes needed to construct such a
counterfactual As such, estimating the impact
of credit participation requires measuring the
difference in the outcome between the treatment
and control groups:
E(Y|D=1) – E(Y|D=0) Where, Y is the outcome and D is the treatment
taking a value of 1 if the treatment has been
received, and 0 if it has not The difference in
the outcome, however, may result from either
the treatment (credit participation), differences
in observable characteristics or differences in
unobservable characteristics Estimates will be
biased if one does not control for the differences
in observable and unobservable characteristics
Differences in observable characteristics result
in an “overt bias”, which can be removed by controlling for observables (Xi) in estimation models (Lee 2005) Thus, the estimation is now formulated as follows:
E(Y| D=1, Xi) – E(Y|D=0, Xi) The estimated impact may also include a “hidden bias” resulting from unobservable characteristics
Models using a randomized selection of treatment and control groups are helpful in this regard, as the randomization allows us to cancel out the differences in both observable and unobservable characteristics However, it is very hard to conduct a randomized test evaluating the impact
of credit due to motivation and contamination problems (Mosley 1997) Hence, there are usually some problems with using non-experimental data due to the non-random implementation of credit programmes and self-selection into credit participation by borrowers Estimates of causality may include a selection bias if credit participation
is correlated with unobserved characteristics that also affect the outcome For instance, households that are better motivated to invest in children’s schooling may have a greater demand for credit
Without an adequate measure of motivation, this hidden factor may make an observable correlation between credit and schooling seem like a causal effect has taken place
In the case of our sample, non-randomized credit participation is not a crucial concern because all the surveyed households have a per capita income of less than VND6 million This means that they are all eligible for preferred credit (i.e., subsidized interest and easy conditions) from government funds Selection by informal lenders and self-selection into credit borrowing due to unobservable factors, however, may still occur
If data on pre-treatment variables of interest are available, researchers may examine differences in these variables in order to determine whether there
is a positive or negative selection on unobserved characteristics (conditional on the observed characteristics) For instance, if YT
0 and YC
0 are the respective outcomes for the treatment and control groups at time 0 (before the treatment),
Trang 5and if E(YT | D=1, Xi) ≠ E(YC
0 | D=0, Xi) is the result after controlling for observable factors, one
should suspect that unobservable confounders
are affecting the treatment and outcomes That
is to say that a “hidden bias” has resulted from
unobservable confounders Lee (2005, p 125)
suggests that controlling for Y0 (together with Xi
on the right-hand side) may to some extent reduce
the hidden bias For the purposes of our study,
pre-treatment data on the variables of interest is not
available but we can use (baseline) pre-treatment
income per capita as a control variable (Mosley
1997; Heckman and Smith 1999):
Yij,t-1 = a + b.Dij,t + I.Xij,t + eij,t-1 (1) Where, Yij is the outcome of interest of household
i in ward j; D is a dummy variable representing
(1) if a household borrows and (0) if it does
not; X is a set of unchanged (or little changed)
control variables over time, such as household
characteristics The coefficient b shows whether
borrowers had a higher or lower income per
capita than non-borrowers prior to participating in
borrowing activities (conditional on their observed
characteristics) If b is positive, that means a
positive selection on unobserved attributes exists:
borrowers tend to be richer than non-borrowers,
which will lead the non-experimental estimators
to overstate the impact of credit participation
We ran a regression of equation (1) and found a
significantly positive b coefficient
III.3 Emprical Method
The propensity-matching method is the most
suitable candidate for cross sectional
non-experimental datasets without good instrument
variables This method forms a control group of
non-participants with observed characteristics that
are similar to participants (the treatment group)
(Dehejia and Wahba 1999, 2002) The main
advantage of the matching method is that one can
draw on existing data sources and so it is quicker
and cheaper to implement Nevertheless, matching
does not control for unobservable characteristics
that may cause a selection bias, and as a result, the
reliability of estimates is reduced (Smith and Todd 2005) The most widely used matching method is propensity score matching (PSM) Other methods
of matching each X (covariate matching) create a problem of high dimensionality, which requires large datasets
The PSM method first estimates the propensity score for each participant and non-participant on the basis of observed characteristics It then compares the mean outcome for participants with the outcome for the matched (similar in terms of scores) non-participants In other words, the purpose of the PSM is to first select comparable non-borrowing households among all non-borrowing households
to generate a control group, and then compare the outcomes for the treatment and matched control groups The crucial assumption is that the outcomes for non-borrowers in the matched control group represent what the borrowers would have experienced without credit participation This
is referred to as unconfoundedness or a conditional independence assumption (CIA) (Rosenbaum and Rubin 1983) In summary, this is the underlying point of propensity score matching: control and treatment units with the same propensity score have the same probability of assignment to the treatment as in randomized experiments (Dehejia and Wahba 1999)
The PSM method may produce estimates with low bias if datasets satisfy three conditions (Dehejia and Wahba 2002): (i) the data for treatment and control groups are collected using the same questionnaire; (ii) the treatment and control groups are drawn from the same locality;
and (iii) the dataset contains a rich set of variables relevant to modelling credit participation and its outcomes Since all households surveyed in this study were poor prior to credit participation, the PSM method should produce less biased estimates than it would for a general sample of households with highly divergent per capita income rates
While the PSM method also allows controlling for potential biases such as non-placement and self-selection (Dehejia 2005; Dehejia and Wahba 2002), it fails to control for unobservable characteristics which may create hidden biases because the scores are calculated on the basis of
Trang 6observed characteristics only (Dias, Ichimura and
Berg 2007) As was mentioned above, observable
characteristics may not fully capture individual
motivation, ability and skills — all of which may
affect the treatment participation Ultimately,
the success of the PSM method depends on how
close the control and treatment group are in terms
of space and time Further, the two groups should
have as little baseline differences as possible
(Lee 2005)
IV Empirical Results
The PSM estimates of the impact on education
and healthcare expenditure are presented in
subsection IV.1 while subsection IV.2 looks at the
impact of formal and informal credit on household
expenditure
IV.1 PSM Estimation
Kernel (with the default bandwidth of 0.06)
and radius matching (with the default radius
of 0.1) results of the impact of microcredit on
education and healthcare spending are discussed
in this subsection.3 Imbens (2004), Lee (2005) and
Rosenbaum and Rubin (1983) note that sets of
controlling covariates should meet the conditions
of matching controlling variables In this paper,
the use of covariates in the score estimation stage
follows discussions in Lee (2005) and Rosenbaum
and Rubin (1983), and Caliendo and Kopienig
(2008) and Bryson, Dorsett and Purdon (2002)
In some cases, interaction terms were also used to
balance the estimated propensity scores
Impact on Education Expenditure Our base
specifications (S1 and S3 in Table 1) use a set of
covariates of household characteristics such as:
the head of the household’s gender, age, education
and marital status; school-aged child ratio, the
number of children; and ward dummies to estimate
the scores Although we do not have panel data
to apply the difference-in-difference matching
estimator (believed to be considerably better than
cross-sectional matching estimators), our attempts
at reducing bias associated with unobservable
characters by including pre-treatment household income and assets may help offset any disadvantage (Imbens and Wooldridge 2009; Mosley 1997) The effects that occur when pre-treatment income and assets are included in the matching are reported in the second (S2) and fourth rows (S4) of Table 1
The changes in the model specifications between
S1 and S3 and between S2 and S4, are to test for the sensitivity of the effect
Figure 1 displays the kernel densities of the propensity scores when pre-treatment income and assets are included alongside the other controlling variables (S4 in Table 1) The propensity scores range from 0.418 to 0.943 and from 0.174 to 0.940 for borrowers and non-borrowers, respectively,4 but the mean scores are not much different (0.761 and 0.675 for borrower and non-borrower groups)
The figure also illustrates a substantial overlap
in the distributions The following estimation of the average effect of the treatment is restricted
to the area of common support, where the two distributions overlap Thus, some non-borrowers who are dissimilar to borrowers are not used in the comparison
The estimates of the average effect of the treatment, on the treated (ATT), are reported in Table 1 There is little difference in the results
of the two matching approaches used When matching just household characteristics and location dummies (S1 and S3), the effect of credit participation on education spending is observed to
be statistically significant at the 1 per cent level
After including the pre-treatment income and assets (S2 and S4) the estimated impact of credit participation declines, but is still significant at the
5 per cent level
According to these PSM estimates, the borrowers, on average, spent about VND81,000
to VND99,000 more on education per month than comparable non-borrowers
Impact on Healthcare Expenditure Figure 2
displays the kernel densities of the propensity scores estimated for evaluating the impact of credit participation on healthcare expenditure.5 The scores are from when the pre-treatment income and assets are included alongside the
Trang 7FIGURE 1 Propensity of Scores for Borrowers and Non-borrowers to Estimate the Effects of
the Treatment on the Treated for Education Expenditure
N ote : The propensity scores of control units outside the area of common support are cut off.
TABLE 1 The Average Effect of the Treatment on Monthly Average Education Expenditure in VND1,000
Using Matching Estimators for the Entire Sample
Control variables in the propensity score estimation Kernel matching Radius matching
Head’s gender, head’s age, head’s education, marital status, 92.696 (31.967)** 98.696 (32.393)**
school-aged child ratio, and ward dummies (S1)
S2=S1plus initial income in log, initial assets in logarithm 85.020 (34.027)* 93.022 (31.506)**
Head’s gender, head’s age, head’s education, marital status, 87.447 (33.875)** 93.179 (34.182)**
number of children from 6 to 18, and ward dummies (S3)
S4=S3 plus initial income in log, initial assets in logarithm 81.232 (34.621)* 86.861 (34.448)*
N otes : Bootstrapped standard errors in parentheses with 1,000 repetitions, statistically significant at 10 per cent (+);
5 per cent (*); and 1 per cent (**) Only a few households (10 households) have 4 or more children aged 6 to 18 years
old To simplify the process, we grouped them with households having 4 kids S i are model specifications.
1 2 3 4
Predicted Probability
Trang 8matches (S4 in Table 2) The propensity scores
range from 0.348 to 0.989 for borrowers and from
0.195 to 0.962 for non-borrowers Once again,
the estimation of the average treatment effect is
restricted to the area of common support where
the distributions overlap
The estimates of the impact of credit participation
on healthcare expenditure are reported in Table 2
The results show that credit participation positively
affects healthcare expenditure They are also
statistically significant regardless of the sets of
covariates and the types of matching approaches
used Borrowers spent about at least VND93,000
more on healthcare than their non-borrowing
counterparts
IV.2 Impact of Formal and Informal Household Credit
In this subsection, the effects of multiple treatments are estimated to contrast the impact
of informal and formal credit on education and healthcare expenditure (Lee 2005) When applying these multiple treatments, we treat credit from formal sources (F) as a full “dose” and credit from informal sources (I) as a partial “dose”.6 Here, we directly compare the formal and informal credit groups, taking the informal credit group as the control group
Estimates of the effects of the multiple treatments
on education expenditure are reported in Table 3
The estimation procedure used here is similar to
FIGURE 2 Propensity of Scores for Borrowers and Non-borrowers to Estimate ATT for Healthcare Expenditure
N ote : The propensity scores of control units outside the area of common support are cut off.
–4
2 1
3 4
Predicted Probability
Trang 9TABLE 2 Average Effect of the Treatment on Monthly Average Healthcare Expenditure in
VND1,000 Using Matching Estimators
Control variables in the propensity score estimation Kernel matching Radius matching
S2=S1 plus initial income in log, initial assets in logarithm 93.082 94.016
S4=S3plus initial income in logarithm, initial assets in log 108.313 112.895
N otes : Bootstrapped standard errors in parentheses with 1000 repetitions, statistically significant at 10 per cent (+);
5 per cent (*); and 1 per cent (**).
S 1 : Head’s gender, head’s age, head’s education, marital status, household size in log, head’s age*gender, ward
dummies.
S 3 : Head’s gender, head’s education, marital status, dummy of child below 6, number of children from 6 to 18 years
old, persons from 18 to 60 years old, dummy of person older than 60 years old, head’s age*education, and ward
dummies.
the one discussed in subsection IV.1: household
characteristics are first used to construct the scores
(S1 and S3) and thereafter, pre-treatment income
and assets are controlled for (S2 and S4) The
estimated effects of informal credit are reported in
columns 2 and 3, and the effects of formal credit
effect are reported in columns 4 and 5
The estimates show that informal credit has
no significant effect on household education
expenditure In contrast, formal credit strongly
affects education expenditure Both kernel
and radius matching estimators display similar
estimates that are statistically significant at the
1 per cent level
To test the results further, we directly compared
the impact of formal credit to informal credit
Estimates of the difference between the impact of
formal and informal credit are shown in the last
column of Table 3 The estimates are consistent
across the specifications of the matching variables
The higher credit level (or treatment level) leads to
a greater positive impact
Likewise, we looked at the impact of formal and informal credit on healthcare spending The estimates for informal credit and formal credit
on health care expenditure are reported in Table
4 The results of the difference in the impact of formal and informal credit are presented in the last column of Table 4 Informal credit has a positive but only marginally significant impact at the 10 per cent level of statistical significance In contrast, the impact of formal credit is more than double that of informal credit (statistically significant at the 10 per cent level)
The use of multiple ordered treatments shows that the higher treatment level (formal credit) has a greater positive impact on healthcare and education expenditure, thus confirming the positive effects of credit on healthcare and education
Trang 10TABLE 3 The Average Effect of Treatment on Monthly Average Education Expenditure in
VND1,000 using Matching Estimators for the Entire Sample
N otes : Bootstrapped standard errors in parentheses with 1,000 replications, statistically significant at 10 per cent (+);
5 per cent (*); 1 per cent (**).
S 1 : Head’s gender, head’s age, head’s education, marital status, ward dummies, school-aged child ratio, and head’s
age*head’s gender.
S 2 : Head’s gender, head’s age, head’s education, marital status, ward dummies, school-aged child ratio, head’s
age*head’s education, initial income in logarithm, initial assets in logarithm.
S 3 : Head’s gender, head’s age, head’s education, marital status, ward dummies, number of children aged 6 to 18 years
old, and head’s age*head’s gender.
S 4 : Head’s gender, head’s age, head’s education, marital status, ward dummies, number of children aged 6 to 18 years
old, head’s age*education, initial income in logarithm, initial assets in logarithm In some cases to meet the balancing
property in estimation of propensity scores we added interaction terms in specifications of the propensity score.
ATTK: Average Treatment Effect on the Treated, Kernel matching.
ATTR: Average Treatment Effect on the Treated, Radius matching.
V Finding Summary and Concluding
Remarks
This paper estimates the impact of credit
participation on education and healthcare
expenditure by the poor in the peri-urban District
9 of Ho Chi Minh City, Vietnam, using data from
a survey designed to meet the conditions for
propensity score matching.7 The results illustrate
that borrowers spent more on education and
healthcare than their non-borrowing counterparts, thus credit participation has a highly positive and significant effect on healthcare and education spending
We focussed on the poor in order to ensure that disparities between the treatment and control groups would be minimal We also controlled for pre-treatment income levels, which, in turn, control for unobservable attributes such as motivation,