rafmacalaba/datause-encoder-data huggingface dataset:
# **6. Robustness Tests**

In this section, we conduct two robustness tests around our main findings. The first robustness test aims to address a potential omitted-variables problem. It is possible that stock liquidity is related to a certain unobserved variable that in turn affects investors’ decision to sell versus hold. In order to address this potential endogeneity problem, we study investor behavior around periods of quasi-exogenous liquidity shocks that are unlikely to affect holding periods directly. Specifically, in section 6.1 we examine how stock liquidity and holding periods change around stock split events.

The second robustness test is meant to address potential selection issues with the US sample. Transaction-level data set used in the US captures only a fraction of the US households’ trades during certain years and hence may be insufficient to test our main predictions. In order to address this criticism, we repeat our main analyses in section 6.2 utilizing another data set which covers all Finnish individual investors’ complete trading records. Using an additional data set from another country also provides us with an “out-of-sample” test of our main findings.

# **6.1 Quasi-exogenous shocks to liquidity**

As we have mentioned earlier, a long line of literature documents a significant reduction in transaction costs and improved liquidity subsequent to stock splits (Schultz 2000, Desai, Nimalendran, and Venkataraman 1998, Kryzanowski and Zhang 1996, Conroy, Harris, and Benet 1990). These studies also show that post-split performance of splitting firms is statistically indistinguishable from that of non-splitting firms with similar characteristics (see for instance, Byun and Rozeff 2003), implying that stock splits do not credibly signal improved performance. This suggests that one plausible motivation for why investors decide to trade splitting stocks more 27
Policy Research Working Paper 9816

# **Abstract**

Proxy-Means Testing (PMT) and Community-Based Targeting (CBT) are among the most widely used methods for poverty targeting in low-income settings. This paper analyzes household data from nine programs implemented in the Sahel region using a harmonized approach to compare PMT and CBT selection as conducted in practice, once geographical targeting has been applied. The results show that the targeting performance measured depends critically on the definition of the targeting objectives, share of beneficiaries selected, and indexes used to evaluate targeting. While PMT performs better in reaching the poorest households based on per capita consumption, it differs little from CBT, or a random or universal allocation of benefits when distances to poverty lines are considered. When aiming to identify food insecure households, most PMT and CBT targeting schemes perform no better than a random allocation of benefits. On the other hand, targeting costs represent only a small share of budgets. Overall, the results emphasize the need to study programs as implemented in practice instead of relying on simulations of targeting performance, as widely used by practitioners and academics. Taken together, the findings suggest that while there may be a need to select households resulting from budget constraints, PMT and CBT contribute little to poverty or food insecurity reduction efforts in poor and homogeneous settings.

This paper is a product of the Social Protection and Jobs Global Practice. It is part of a larger effort by the World Bank to provide open access to its research and make a contribution to development policy discussions around the world. Policy Research Working Papers are also posted on the Web at http://www.worldbank.org/prwp. The authors may be contacted at pschnitzer@worldbank.org and quentin.stoeffler@um6p.ma.

_The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about development issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and its affiliated organizations, or those of the Executive Directors of the World Bank or the governments they represent._ Produced by the Research Support Team
PUB were unbundled and corporatized. In 2001, a new statutory board, the Energy Market Authority was established to regulate the electricity and gas industries as well as operate the electricity system. Its subsidiary company Energy Market Company Pte Ltd operates the wholesale electricity market. There are at present seven generation licensees and seven retail licensees.

Singapore relies on Malaysia for supply of more than half of its water consumption each day. The two water treaties with Malaysia date back to the early 1960s and were part of the dissolution terms agreed at the separation of the two countries in 1965. The terms of the agreement, in particular the price of raw water (3 Malaysia sen per 1,000 gallons or 4,550 liters), have been a key irritation in the bilateral relations for years. In a bid to demonstrate that it can be self-sufficient in water, the PUB has embarked on water recycling on a limited scale (`newater’ has been introduced into reservoirs since early 2003), a desalination plant project, as well as building an elaborate drainage system to capture rain water.

# **Education and labor**

Education is highly subsidized and constitutes the second largest item of government expenditure (after defense). The percentage of students enrolled in a local university has increased markedly from 7.7 percent of each cohort in 1985 to 21% percent in 2002. The government’s plans are for 25 percent of each cohort to be able to enjoy the benefits of university education. Manpower planning is effected through detailed quotas on the number of students to be admitted to specific programs (law, medicine, architecture, civil engineering, computer engineering, etc) at the tertiary institutions. A new agency, the Singapore Workforce Development Agency was established in 2003 with the specific purpose of enhancing workforce skills through `developing a comprehensive, market-driven and performance-based adult continuing education and training framework’ (Ministry of Manpower website).

While there are no official statistics for the foreign component of the workforce, the population data reveals that 19% of the 4.17 million people in Singapore are foreigners. Indeed, given the small population base in Singapore, it has always relied on foreigners to perform various jobs in the economy. Since the late 1990s, as part of its move to build up the innovative economy, it has also embarked on an aggressive “foreign talent” policy, to attract foreigners who possess the necessary skills for innovation-related, high value-added work. As the Ministry of 9
Furthermore there was a 1.7 percent decline in investment spending and a 1.2 percent decline in the intermediate input demand. Thus an increase in world prices of agricultural commodities causes a decline in prices of other commodities that compete for resources.

For these products quantity of supply and price moves in the same direction. This implies a higher export demand for these goods. A comparison of the share of exports and imports in total production, represented in Table 4.5., reveals this fact. The increase in exports is relatively higher for maize, pulses and other animal products while the increase in imports is minimal.

**Table 4.5. Percentage change in share of exports and imports in total production**

|||**Expo**<br>|**rt**<br>||**Impor**<br>|**t**<br>|
|---|---|---|---|---|---|---|
||**Base**|**Sc. 1**|**Base/Sc.1**|**Base**|**Sc. 1**|**Base/Sc.1**|
|**Wheat**|0.01|0.02|3.42|8.98|2.63|0.29|
|**Barley**|2.32|3.69|1.59|0.93|0.56|0.61|
|**Maize**|1.58|2.92|1.85|68.56|35.95|0.52|
|**Other grains**|0.07|0.11|1.55|8.17|5.28|0.65|
|**Pulses**|11.16|22.19|1.99|0.88|0.32|0.36|
|**Tobacco**|24.05|23.45|0.97|14.60|15.21|1.04|
|**Sugar beet**|0.00|0.01|1.87|0.22|0.12|0.53|
|**Cotton (raw)**|6.97|8.60|1.23|37.26|29.15|0.78|
|**Oil seeds**|4.37|5.58|1.28|18.54|14.13|0.76|
|**Potatoes**|0.93|1.00|1.07|0.30|0.28|0.94|
|**Vegetables**|1.97|2.08|1.06|0.38|0.36|0.94|
|**Fruits**|7.09|7.47|1.05|0.64|0.60|0.94|
|**Nuts**|19.61|20.34|1.04|0.62|0.58|0.94|
|**Other crops**|0.06|0.13|2.10|0.13|0.06|0.48|
|**Milk**|0.04|0.07|1.66|0.38|0.23|0.60|
|**Cattle Meat**|0.02|0.02|1.29||||
|**Other Bovine Meat**|1.24|1.73|1.40|0.01|0.01|0.71|
|**Poultry and Eggs**|2.15|2.89|1.35|0.55|0.40|0.73|
|**Other Animal Prod.**|14.58|20.14|1.38|11.40|7.16|0.63|
|**Other Agricultural Prod.**|3.64|5.52|1.52|5.80|3.66|0.63|
|**Food Production**|8.04|6.57|0.82|3.42|4.31|1.26|
|**Mining**|18.47|18.49|1.00|371.40|371.04|1.00|
|**Consumer Manufac.**|33.13|32.67|0.99|9.79|10.06|1.03|
|**Int. and Cap. Goods**|23.00|22.88|0.99|57.24|57.71|1.01|
|**Private Services**|12.72|12.52|0.98||||

_Source: Results from TACOGEM-W._ The net effect of increasing world food prices on household welfare is also controversial. Non-farm households are likely to be adversely affected by increasing food prices. However, increasing export demand has the reverse effect by changing the factor allocation and causing a 39
Fig **5a:** The trend of employment and real GDP in the agriculture sector.

<!-- Start of picture text --> 60 150<br>18 1 9 145.2<br>i 40<br><- = 140 80 o LO)<br>E530 .0-*<br>2 o ' 135 °60 o o<br>13 20 10~~~~~~~~~~~~~~ year ,130<br>0 125<br>1984 1985 1986 1987 1988 1989 1990<br>years<br>agri. emp - -o - agri GDP<br>Fig 5b: The trend of employment and Real GDP in<br>the industrial sector<br>120<br>.2<br>0- 80C, o .<br>E S<br>~p 60 0 0 3<br>40 C<br>S 20 3<br>0 -- ~~~~~~~~~~~~25<br>1984 1985 1986 1987 1988 1989 1990<br>years<br>14 20 150.<br>- - O- .ind-ermp -.-- ind. GDP<br><!-- End of picture text --> Fig 5c: The trend of employment and real GDP in the services sector in Ghana.

<!-- Start of picture text --> 400 200<br>350 0<br>300 - 150.2<br>250-<br>~S200 -1 00 o :<br>E 150 -- 0- -0<br>w 100 50 *R<br>50<br>0 0<br>1984 1985 1986 1987 1988 1989 1990<br>Years<br>- -o - serv. emp -- serv. GOP<br><!-- End of picture text --> 28
Although state-owned banks are generally found to have problems in providing<sup>financialservices and</sup> often require significant government subsidies, there are some exceptional<sup>cases of state-ownedinstitutions that</sup> are able to meet their SME lending objectives without explicit government<sup>subsidies.The Mauritius Commercial</sup> Bank (MCB) has less than 5% direct government share, and is a profitable<sup>andefficientinstitution (Mauritius</sup> Commercial Bank Annual Report 2002). In addition, the Thai Bank for Agriculture and Agricultural Cooperatives (BAAC) is a rare case of a development bank with mandated<sup>lendingobjectivesthatdoesnot</sup> depend on subsidies and succeeds in providing credit to rural farners.<sup>In 1998, the BAAC extended loans to more</sup> than 80% of Thailand's farming households (Townsend and Yaron<sup>2001).</sup> 29
exposure villages), and 33% of interested households being offered access to warrantage (referred to as low exposure villages). Baseline and follow-up data were collected from 528 households, who participated in the lottery to gain access to warrantage (hereafter referred to as lottery participant households). We also collected data from 183 households who did not partake in the household randomization (hereafter referred to as non-participant households).

Using the household-level randomization, we find that treated households choose primarily to store sorghum and maize grains through the warrantage storage mechanism. These crops are common in the area and exhibit significant historical price volatility. Take-up of the storage element of warrantage was close to universal and enabled these households to shift from home storage to storage in village warehouses. Credit utilization, on the other hand, was far lower, with only 38 percent of treated households taking up the credit offer. Through the increased storage of key grains, we find suggestive evidence of fewer sales immediately after harvest and more sales at the time of destockage, when prices are higher. Higher sales prices translate into higher crop revenues among treated households. With more cash on hand, treated households invest more in human capital, specifically education expenditure. We find no impact on food expenditure and no significant impact on a series of food security indicators, although the general pattern of results is positive. Alongside the educational investments, treated households increased their livestock holdings and increased input expenditures for the subsequent agricultural season.

To examine the spillover effects of the introduction of warrantage, we compared nontreated households in low exposure villages to those in high exposure villages. Spillover effects attributable to greater village-level exposure to warrantage are limited. Also, in contrast to anecdotal claims, access to warrantage does not meaningfully affect village-level relations or sharing norms within the community. We conduct a simple cost-effectiveness calculation which 3
PPR Working Paper Series

||Title|Author|Date|Contact|
|---|---|---|---|---|
|WPS13|Objectives and Methods of a World||||
||Health Survey|Trudy Harpham<br>Ian Timaeus|June 1988|A. Menciano<br>33612|
|WPS14|The Optimal Currency Composition<br>of<br>Externai Debt|Stijn Claessens|June 1988|S. Berteismeler<br>33768|
|WPS15|Stimulating<br>Agricultural<br>Growth and<br>Rural Development in Sub-Saharan<br>Africa|Vijay S. Vyas<br>Dennis CaFley|June 1988|H. Vallanasco<br>37591|
|WPS16|Antidumping<br>Laws and Developing<br>Countries|Patrick M4esserlin|June 1988|S. Torrijos<br>33709|
|WPS17|Economic Development and the Debt<br>Crisis|Stanley Fischer|June 1988|C. Papik<br>33792|
|WPS18|China's Vocational<br>and Technical<br>Training|Harold Noah<br>John Middleton|June 1988|W. Ketema<br>33651|
|WPS19|Cote d'lvoire's Vocational<br>and<br>Technical Education|Christiaan<br>Grootaert|<br>June 1988|R. Vartanian<br>34678|
|WPS20|<br>Imports and Growth in Africa|Ramon Lopez<br>Vinod Thomas|June 1988|61679|
|WPS21|Effects of European VERs on Japanese<br>Autos|Jaime de Melo<br>Patrick Messerlin|June 1988|S. Fallon<br>61680|
|WPS22|Methodological<br>Problems in Cross-<br>Country Analyses of Economic Growth|Jean-Paul<br>Azam<br>Patrick Guillaumont<br>Sylviane Guillaumont|June 1988|E. Zamora<br>33706|
|WPS23|Cost-Effective<br>Integration<br>of<br>Immunization<br>and Basic Health Services<br>in Developing<br>Countries: The Problem<br>of Joint Costs|A. Mead Over, Jr.|July 1988|N. Jose<br>33688|
journals and the top 27 specialized development journals are cited, on average, 13 and 18 times respectively, and the Bank ranks 12<sup>th</sup> and first respectively by this measure. As previously noted, Barrett et al.’s list includes several general journals, with limited coverage of development. Focusing on articles published in the journals on Barrett et al.’s list but classified by SSCI as “Development and Planning”, the Bank ranks second just in average citations. The Bank ranks first on the h-index for the top 16 development economics journals when the focus is on articles in Planning and Development, and first on the h-index for the 27 development journals.

The h-index reveals that the Bank has published 83 articles in journals indexed by SSCI each of which has been cited at least 83 times. In terms of this institutional h-index, the Bank ranks ninth among the universities and first among the international agencies.

We have noted the Bank’s prominence in work on Africa (Table 2). We also found that this work on Africa is heavily cited. The Bank’s h-index for Africa research is higher than all universities except Harvard (details available from the authors). In terms of the h-index the Bank ranks third for China research (only behind Harvard and Stanford). And the Bank is only behind Harvard for research on India.

We also identify selected themes where the Bank has concentrated its research effort, namely poverty (third rank amongst universities in terms of h), inequality (second), growth (second), trade (ninth), education economics (second), health economics (second); in each of these topics the Bank’s h-index is higher than any other international institution working on finance and/or development.

# **Bibliometrics of World Bank authors**

So far we have focused on World Bank _publications_ ; we turn now to their _authors_ . **_Bank authors compared to authors elsewhere_** Most journal articles where the World Bank is listed in the author’s field or as the author’s affiliation are by Bank staff. There are, we think, only a few exceptions, the most visible being the staff of the tropical diseases research program supported jointly by the Bank, WHO, UNICEF and UNDP.<sup>19</sup> We have eliminated these (very productive) individuals from our

> 19  The UNICEF/UNDP/World Bank/WHO Program for Research and Training in Tropical Diseases (TDR) was started in 1975-76 with the two-fold objective of research and development of new and improved tools for the control of major tropical and neglected diseases and the strengthening of national research capabilities in countries where these diseases are endemic. The main diseases covered were: leprosy, leishmaniasis, schistosomiasis, human

22
**Table 4: Technical efficiency indicators for Vietnam’s distribution power companies, 2011 to 2017**

||||**T**|**arget Value**|**s**|**Values as of**|
|---|---|---|---|---|---|---|
|||**Unit**|**2011**|**2015**|**2018**|**Dec 2017**|
||NPC||5145|4947|4656|1826|
||CPC||3631|3436|3234|2117|
|**SAIDI**|SPC|Minutes|6958|5871|5525|777|
||HCMPC||1682|716|384|130|
||HNPC||299|296|291|268|
||NPC||19.8|19.2|18.65|14.91|
||CPC||23.53|22.26|20.95|5.72|
|**SAIFI**|SPC|Times|24.3|22.9|21.6|3.235|
||HCMPC||7.62|3.82|2.5|0.93|
||HNPC||1.73|1.7|1.67|1.63|
||NPC||60|52|40|42|
|**Voltae**|CPC||0|0|0|0|
|**g**<br>**fltti***|SPC|Times/Year|25|10|4|4|
|**ucuaon**|HCMPC||0|0|0|0|
||HNPC||0|0|0|0|
||NPC||24.38|16.59|11.39|11.06|
|**Ditibti**|CPC||13.58|11.67|10.39|4.87|
|**sruon**<br>**l**|SPC|Percentage|10.24|8.66|7.6|4.44|
|**osses**|HCMPC||7.86|6.44|5.5|3.72|
||HNPC||19|14.8|12|9.9|

* Voltage fluctuations outside +/-5 percent at 110 kV/MV transformers in project areas

Source: World Bank (2018).

**Efficiency of thermal power plants has increased from 22 percent in 1990 to 45 percent in 2014.** See Figure 10. Installed thermal capacity is only partly used to balance the variability of hydropower. Generation companies show high capacity factors but low load factors especially for coal and gas (<53 percent in 2011-2012).<sup>9</sup> Suggested reasons for low load factors include low capacity in the 500 kV north-south transmission line, and high reserve generation requirements related to either security or cycling requirements. EVN expects a shift towards relatively more gas- and coal-fired generation, which would increase load factors as less reserves are needed to manage fluctuating hydrological and variable renewables conditions.

**Figure 10: Thermal efficiency of fossil-fuel power plants in Vietnam, 1990-2014**

<!-- Start of picture text --> 50%<br>40%<br>30%<br>20%<br><!-- End of picture text --> 9 Capacity factor is total output divided maximum theoretically possible output for a given year (or other period). Load factor is average load divided by actual maximum load, for a given year (or other period).

23
less flexible. We consider in turn three possible sets of such firms, i.e. smaller firms, firms that import inputs less frequently on average, and firms that produce higher quality goods, as proxied by a higher unit value.

# **Firms participating in global value chains**

To test whether the negative effects of NTMs are driven mostly by firms participating in global value chains, we exploit an unique advantage of the Indonesian customs data which includes information on whether the firm is a producer or not.<sup>15</sup> We re-run our main specification 1 but separately for firms that participate in global value chains and firms that are not producers. The results are reported in Table 4. Most of the negative effects of NTMs on exports to Japan are driven by firms that participate in global value chains as those firms import goods for production that is then exported. The non-producers are barely affected by the NTMs, with the exception of SNI certification requirements, whose effect is negative and significant also for non-producers.

As Chinese exchange rate depreciates, Chinese exports become cheaper, and firms that participate in global value chains that face NTMs on their imported inputs, have a harder time adjusting production to the new competitive environment. Their revenue thus falls, as reflected in the negative effect of NTMs on export revenues for firms participating in global value chains. Take the 10% devaluation example, using pre-shipment inspections. For two firms participating in global value chains selling products exposed to average Chinese competition (.10), the firm at the median level of PSI exposure faces a 0.32% decline in its export value and a firm above the 90<sup>_th_</sup> percentile faces a 1.99% decline in its export value. On the other hand, for two firms who are pure traders selling products exposed to average Chinese competition (.37), these numbers are near zero and 0.64% respectively.

Table 5 reports the magnitudes of the elasticity of response of exports to exchange rate shocks for firms participating in global value chains and pure traders respectively when

> 15For example, pure trading firms are firms that only engage in trade without producing.

25
2 efficiency are plausible, empirical support for them is not available.' One is left wondering whether the received wisdom is more a matter of faith than fact.

The lack of clear evidence is not accidental. To examine the intra-industry effects of trade reforms directly, one must make "before and after' comparisons of a large sample of plants. Sufficient data are rarely available for the appropriate countries at the appropriate times. Fortuitously, however, the Chilean trade liberalization of 1974-79 was preceded and followed by industrial censuses, providing a natural experiment. This paper is an effort to document the evidence that emerged.

The paper is divided into three remaining sections. After some background on Chilean reforms, section II presents descriptive measures of the size distribution and productivity of each industry in each census year. Changes in these measures across census years are then correlated with industry-specifi **c** hanges in effective protection rates. The results are suggestive, but suffer from conceptual problems, measurement error and missing data problems. Hence section III corrects for these shortcomings and re-examines patterns of association. The results reinforce and extend the findings in section II: Although overall industrial efficiency did not improve between the two census years, the 3-digit industries that underwent relatively large reductions in protection improved relative to others.

# II. A GLANCE AT THE DATA

# A. Changes in the Chilean Economy Between The Census Years

In this section we take a first look at the data to familiarize the reader with general magnitudes and sources of variation. But before