## Box 1: Gravity Model: Explanation of Variables

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---

### Trade variables and regional dummies
- LTrTOTij — Log of total trade flows, merchandise and services, in current US dollars between Country i and Country j
- LTrMRCij — Log of total merchandise trade flows in current US dollars between Country i and Country j
- LTrMANUij — Log of trade flows of manufacturing goods in current US dollars between Country i and Country j
- LTrPRIPDij — Log of trade flows of primary commodities in current US dollars between Country i and Country j
- LTrSERVij — Log of trade flows of services in current US dollars between Country i and Country j
- LAC — Dummy variable taking the value of one if exporting Country i is in the Latin American and Caribbean region, zero otherwise
- SA — Dummy variable taking the value of one if exporting Country i is in South America, zero otherwise
- CA — Dummy variable taking the value of one if exporting Country i is in Central America, zero otherwise
- MEX — Dummy variable taking the value of one if either the exporting Country I or the importing Country j is Mexico
- CAR — Dummy variable taking the value of one if exporting Country i is in the Caribbean sub-region, zero otherwise

### Gravity variables (size, distance, commonalities)
- LGDPi / LGDPj — Log of GDP, in current US dollars, of Country i / Country j
- LPOPi / LPOPj — Log of population of Country i / Country j
- LDISTANCE — Log of distance (km) between the capital cities of Countries i and j
- LANG — Dummy variable taking the value of one if Countries i and j share a common language, zero otherwise
- BORDER — Dummy variable taking the value of one if Countries i and j share a common border, zero otherwise
- LANDLLi / LANDLLj — Dummy variable taking the value of one if Country i / Country j is landlocked, zero otherwise

### Trade policy variables (TP)
- TRIj — Non-tariff trade barrier index for importing Country j from the Measure of Aggregate Trade Restrictiveness (MATR) database
- MFNTj — Most favored nation (MFN) tariff imposed by importing Country j (weighted by trade values)
- RTA — Dummy variable taking the value of one if both Countries i and j have a regional trade agreement in place, zero otherwise
- NAFTA — Dummy variable taking the value of one if both Countries i and j are members of the NAFTA trade agreement, zero otherwise

### Infrastructure, customs, digital access, and firm constraints
- LPITRANSi / LPITRANSj — Quality of trade and transport infrastructure (World Bank LPI) for exporting Country i / importing Country j
- LPICUSTi / LPICUSTj — Efficiency of customs and border clearance (World Bank LPI) for exporting Country i / importing Country j
- BESTRANSi / BESTRANSj — Percent of firms identifying transport as a major or very severe constraint
- BESCUSTi / BESCUSTj — Percent of firms identifying customs regulations and clearance as a major or very severe constraint
- MBUSERSi / MBUSERSj — Number of mobile broadband users per 100 inhabitants
- BESFINi / BESFINj — Percent of firms identifying access to finance as a major or very severe constraint
- BESELECi / BESELECj — Percent of firms identifying electricity as a major or very severe constraint

### Quality, human capital, and governance
- BESSKLABi / BESSKLABj — Percent of firms identifying an inadequately educated workforce as a major or very severe constraint
- HCIi — Human Capital Index for exporting Country i, from the Penn World Tables
- BESCORRi / BESCORRj — Percent of firms identifying corruption as a major or very severe constraint
- BESCRIi / BESCRIj — Percent of firms identifying crime, theft and disorder as a major or very severe constraint
- BESPOLINSTi / BESPOLINSTj — Percent of firms identifying political instability as a major or very severe constraint
- BESGOVAvgi / BESGOVAvgj — Simple average of the three WBES governance indicators for Country i / Country j
- WGICORRi / WGICORRj — WGI control of corruption indicator
- WGIPOLSTi / WGIPOLSTj — WGI political stability indicator
- WGIROLi / WGIROLj — WGI rule of law indicator
- WGIGOVAvgi / WGIGOVAvgj — Simple average of the three WGI governance indicators for Country i / Country j

---

### Baseline gravity results — summary and key coefficients (Tables 1–3)
- Baseline finding: Significant under-trading only in the case of services for Latin America and the Caribbean (LAC) as a whole (Figure 8). Note: ** statistically significant at the 5 percent level. Otherwise, not statistically significant.
- Selected baseline coefficients (coef; tstat) — Merchandise and Services (Table 1):
  - LGDPi: 0.778***; 18.86 | 0.770***; 19.72 | 1.048***; 29.33 | 1.046***; 29.50
  - LGDPj: 0.813***; 14.36 | 0.803***; 15.33 | 1.065***; 36.81 | 1.063***; 36.65
  - LPOPi: -0.00525; -0.103 | -0.00619; -0.125 | -0.370***; -8.670 | -0.369***; -8.661
  - LPOPj: -0.126***; -2.595 | -0.125***; -2.705 | -0.369***; -10.65 | -0.368***; -10.67
  - LDISTANCE: -0.427***; -7.066 | -0.426***; -7.193 | -0.597***; -19.20 | -0.596***; -19.26
  - LANG: 0.290***; 2.739 | 0.327***; 3.308 | 0.835***; 10.09 | 0.841***; 10.21
  - BORDER: 1.159***; 7.006 | 1.098***; 7.462 | -0.0285; -0.232 | -0.0330; -0.273
  - LANDLLi: -0.134; -1.238 | -0.144; -1.321 | -0.284**; -2.445 | -0.286**; -2.462
  - LANDLLj: -0.283***; -2.593 | -0.287***; -2.647 | -0.167; -1.301 | -0.168; -1.307
  - Observations: 21,010 | 21,010 | 13,687 | 13,687
  - R-squared: 0.456 | 0.495 | 0.751 | 0.752
- Gauging intra-regional trade (Table 3):
  - intra-LAC dummy: -0.426**; -1.991 (merchandise) | -0.521***; -3.149 (services)
  - Observations: 21,010 | 13,687
  - R-squared: 0.459 | 0.751

---

### Benchmarking constraints (Figure 10; period averages 2015-2019)
- Data notes: MFN tariffs are rates, MATR is a count of restrictions, LPI is an index, firm constraints are shares of firms reporting constraints.
- LAC median vs EMDE (excluding LAC) 25th and 75th percentiles:
  - In most measures, LAC countries stand between best and worst EMDE performers, indicating scope for improvement.
  - MATR: median LAC country stands close to the best performers among non-LAC EMDEs (relatively low non-tariff restrictions).
  - Electricity as a constraint and governance as a constraint: median LAC country stands closer to the worst performers among EMDEs.

---

### Augmented gravity regressions — how constraint sets affect sub-regions (Figures 11–14; Tables 4–13)
- Method: Baseline gravity augmented with four sets of variables — trade policy; transport infrastructure and customs; access to and quality of factor inputs; governance indicators.
- Trade policy (Tables 4–6) — selected coefficients:
  - RTA: 0.662***; 6.793 | 0.0474; 0.560 (Table 4, merchandise and services)
  - TRIj: -0.292*; -1.671 | -0.0413; -0.385
  - MFNTj: -0.0393**; -1.972 | -0.0320*; -1.843
  - NAFTA (Table 6): 0.0258; 0.120 | 1.142***; 4.436 (reported in specific columns)
  - R-squared increases when trade-policy variables included (e.g., Table 4 R-squared: 0.495 | 0.555)
- Transport and customs (Tables 7–9) — selected coefficients:
  - LPITRANSi: 3.602***; 3.666 | -2.225***; -3.466 (Table 7, different columns)
  - LPITRANSj: 2.292**; 2.533 | -1.398*; -1.690
  - LPICUSTi: -1.501**; -2.237 | 2.748***; 5.451
  - LPICUSTj: -0.571; -0.811 | 1.312**; 2.010
  - MBUSERSi: 0.00287*; 1.648 (Table 8, some columns)
- Factor inputs and digital infrastructure (Tables 9–11) — selected coefficients:
  - BESFINi: 0.00263; 0.511 | -0.00413; -1.221
  - BESFINj: 0.00413; 1.124 | 0.00866**; 2.551
  - HCIi: 0.483***; 3.730 | -0.401***; -4.272
  - BESELECi: -0.00807***; -3.212 | -0.00154; -0.680
  - BESELECj: -0.00248; -1.042 | -0.00772***; -2.779
  - TABLE 10 selected: BESFINi: -0.0180***; -3.711 | 0.0397***; 5.806 ; HCIi: 0.435***; 4.020 | 0.702**; 2.053
- Governance indicators (Tables 11–13) — selected coefficients:
  - BESGOVAvgi: -0.00873***; -2.988 (Table 11)
  - BESGOVAvg i: -0.0157***; -6.370 | 0.00851*; 1.907 (Table 12)
  - BESTRANSi: -0.0161***; -3.167 (Table 13)
  - BESCUSTj: 0.0260***; 2.642 (Table 13)

#### Sub-region specific augmentation outcomes (summary of Figures 11–14)
- South America:
  - Trade policy variables: negligible impact on regional dummy coefficients.
  - LPI transport and customs: regional dummy coefficient halves for manufactured goods but significant under-trading remains; under-trading in services fully explained by LPI.
  - Digital infrastructure (mobile broadband users): marginal impact.
  - Factor inputs (WBES electricity and access to finance, plus HCI): notable reduction in regional dummy for manufacturing (not services).
  - WBES governance average: inclusion makes coefficients on regional dummies statistically insignificant across all product groups.
- Central America:
  - Trade policy variables and WBES governance: little impact; regional dummies continue to show significant under-trading for manufactured goods and primary commodities.
  - LPI index, particularly transport infrastructure: notably reduces regional dummy for manufacturing but under-trading remains significant; marginal impact on primary commodities.
  - Human Capital Index and WBES electricity/access to finance: little impact on regional dummy values despite many factor variables being statistically significant and of expected sign.
- Mexico:
  - Trade policy variables: fully explain over-trading in merchandise trade (manufactured goods).
  - Addition of NAFTA dummy: implies significant under-trading in primary commodities.
  - WBES governance average: reduces extent of under-trading in primary commodities somewhat.
- Caribbean:
  - Trade policy variables and factor input variables: do not explain under-trading in merchandise trade or services.
  - WBES governance variables: do not explain under-trading.
  - LPI transport and customs variables: regional dummy for merchandise trade becomes statistically insignificant (helps explain under-trading in manufactured goods); no notable impact on services.

---

### Robustness checks (Tables 14–16) — replacements and findings
- Replacements used in robustness checks:
  - Replace World Bank LPI index variables with WBES transport and customs survey results (Table 14).
  - Replace Human Capital Index with WBES inadequately educated workforce survey result (Table 15).
  - Replace WBES governance indicators with WGI governance indicators (Table 16).
- Robustness outcomes (selected):
  - Results generally less satisfactory with alternative variables.
  - South America:
    - WBES transport and customs variables fully explain under-trading in manufacturing but negligible impact for services.
    - WBES inadequately educated workforce variable shows statistically significant sign opposite to expectations for South America.
    - WGI governance indicators help explain some under-trading in services, but not in merchandise trade.
  - Central America and Caribbean:
    - WBES transport and customs variables have marginal impacts.
    - WBES inadequately educated workforce variable shows no notable impact on regional dummies.
    - WGI governance indicators do not explain under-trading.

---

### Key empirical conclusions (Section VII)
- Baseline regressions (no policy/constraint variables): significant evidence of under-trading in LAC only for services.
- Disaggregation by sub-region reveals broader under-trading:
  - South America: significant under-trading in merchandise goods (particularly manufacturing) and services.
  - Caribbean: significant under-trading across all product groups (merchandise trade and services).
  - Central America: significant under-trading in merchandise goods (manufactured goods and primary commodities), but not services.
  - Mexico: significant over-trading in manufactured goods (baseline).
- LAC’s under-performance in trade primarily emanates from intra-regional trade rather than inter-regional trade.
- Constraint variables explain parts of under-trading:
  - Poor transport infrastructure and inefficiencies in customs clearance (LPI transport and customs variables) explain a significant part of under-trading in manufactured goods for South America and the Caribbean.
  - WBES governance indicators significant in explaining under-trading in manufactured goods and services for South America, but not for Central America or the Caribbean.
  - Access to factor inputs cannot fully explain under-trading for any sub-region, though HCI reduces under-trading in manufactured goods for South America.
  - For Mexico, trade policy variables fully explain over-trading in manufactured goods; NAFTA dummy introduction implies significant under-trading in primary commodities (possible resource re-allocation effect).
- Research gaps identified:
  - Further research needed to understand (i) factors underpinning Central America’s and the Caribbean’s underperformance in trade, and (ii) the benefits of removing constraints behind LAC’s trade underperformance.

---

### Annex I — Selected model fit and observation counts (Tables 1–16)
- Table 1 observations and R-squared: Observations: 21,010 | 21,010 | 13,687 | 13,687; R-squared: 0.456 | 0.495 | 0.751 | 0.752
- Table 2 observations and R-squared: Observations: 21,010 (all columns); R-squared: 0.418 | 0.459 | 0.265 | 0.271
- Table 7 observations and R-squared (transport/customs): Observations: 15,453 | 15,453 | 11,389 | 11,389; R-squared: 0.557 | 0.618 | 0.751 | 0.754
- Table 9 observations and R-squared (digital/infrastructure): Observations: 10,350 | 10,350 | 8,501 | 8,501; R-squared: 0.509 | 0.520 | 0.714 | 0.716
- Table 14 observations and R-squared (robustness): Observations: 12,870 | 12,870 | 9,900 | 9,900; R-squared: 0.507 | 0.521 | 0.713 | 0.711
- Table 15 observations and R-squared (WGIGOV robustness): Observations: 20,460 | 20,460 | 13,687 | 13,687; R-squared: 0.556 | 0.557 | 0.752 | 0.749

*Source: wpiea2024032-print-pdf - Box 1: Gravity Model: Explanation of Variables*

### Box 1: Gravity Model: Explanation of Variables

### Box 1: Gravity Model: Explanation of Variables

### Trade variables
- LTrTOTij — Log of total trade flows, merchandise and services, in current US dollars between Country i and Country j
- LTrMRCij — Log of total merchandise trade flows in current US dollars between Country i and Country j
- LTrMANUij — Log of trade flows of manufacturing goods in current US dollars between Country i and Country j
- LTrPRIPDij — Log of trade flows of primary commodities in current US dollars between Country i and Country j
- LTrSERVij — Log of trade flows of services in current US dollars between Country i and Country j
- LAC — Dummy variable taking the value of one if exporting Country i is in the Latin American and Caribbean region, zero otherwise
- SA — Dummy variable taking the value of one if exporting Country i is in South America, zero otherwise
- CA — Dummy variable taking the value of one if exporting Country i is in Central America, zero otherwise
- MEX — Dummy variable taking the value of one if either the exporting Country I or the importing Country j is Mexico
- CAR — Dummy variable taking the value of one if exporting Country i is in the Caribbean sub-region, zero otherwise

### Gravity Variables
- LGDPi / LGDPj — Log of GDP, in current US dollars, of Country i / Country j
- LPOPi / LPOPj — Log of population of Country i / Country j
- LDISTANCE — Log of distance (km) between the capital cities of Countries i and j
- LANG — Dummy variable taking the value of one if Countries i and j share a common language, zero otherwise
- BORDER — Dummy variable taking the value of one if Countries i and j share a common border, zero otherwise
- LANDLLi / LANDLLj — Dummy variable taking the value of one if Country i / Country j is landlocked, zero otherwise

### Trade Policy Variables (TP)
- TRIj — Non-tariff trade barrier index for importing Country j from the Measure of Aggregate Trade Restrictiveness (MATR) database computed by Estefania-Flores and others (2022).
- MFNTj — Most favored nation (MFN) tariff imposed by importing Country j on imports from Countries not having a preferential trade / tariff agreement with Country j (weighted by trade values across import lines)
- RTA — Dummy variable taking the value of one if both Countries i and j have a regional trade agreement in place, zero otherwise
- NAFTA — Dummy variable taking the value of one if both Countries i and j are members of the NAFTA trade agreement, zero otherwise

### Infrastructure and Customs
- LPITRANSi / LPITRANSj — Value of the quality of trade and transport infrastructure component of the World Bank’s International Logistics Performance Index (LPI) for exporting Country i / importing Country j. Higher values denote better infrastructure.
- LPICUSTi / LPICUSTj — Value of the efficiency of customs and border clearance component of the World Bank’s International Logistics Performance Index (LPI) for exporting Country i / importing Country j. Higher values denote higher efficiency.
- BESTRANSi / BESTRANSj — Percent of firms in Country i / Country j that trade that identify transport as a major or very severe constraint on the operations of their business
- BESCUSTi / BESCUSTj — Percent of firms in Country i / Country j that trade that identify customs regulations and clearance as a major or very severe constraint on the operations of their business
- MBUSERSi / MBUSERSj — Number of mobile broadband users per 100 inhabitants in Country I Country j

### Quality and Access of Factors of Production
- BESFINi / BESFINj — Percent of firms in Country i / Country j that trade that identify access to finance as a major or very severe constraint on the operations of their business
- BESELECi / BESELECj — Percent of firms in Country i / Country j that trade that identify electricity as a major or very severe constraint on the operations of their business

*Source: wpiea2024032-print-pdf - Box 1: Gravity Model: Explanation of Variables*

### Box 1: Gravity Model: Explanation of Variables (cont.)

### Box 1: Gravity Model: Explanation of Variables (cont.)

### Variables (selected)
- BESSKLABi / BESSKLABj: Percent of firms in Country i / Country j that trade that identify an inadequately educated workforce as a major or very severe constraint on the operations of their business
- HCIi: Human Capital Index for exporting Country i, from the Penn World Tables
- Governance and Institutions:
  - BESCORRi / BESCORRj: Percent of firms in Country i / Country j that trade that identify corruption as a major or very severe constraint on the operation of their business
  - BESCRIi / BESCRIj: Percent of firms in Country i / Country j that trade that identify crime, theft and disorder as a major or very severe constraint on the operation of their business
  - BESPOLINSTi / BESPOLINSTj: Percent of firms in Country i / Country j that trade that identify political instability as a major or very severe constraint on the operation of their business
  - BESGOVAvgi / BESGOVAvgj: Simple average of the above three governance indicators for Country i / Country j from the World Bank’s Business Enterprise Surveys
  - WGICORRi / WGICORRj: World Governance Indicator (WGI) aggregate indicator for Country i / Country j on control of corruption
  - WGIPOLSTi / WGIPOLSTj: WGI aggregate indicator for Country i / Country j on political stability and absence of violence / terrorism
  - WGIROLi / WGIROLj: WGI aggregate indicator for Country i / Country j on rule of law
  - WGIGOVAvgi / WGIGOVAvgj: Simple average of the above three WGI governance indicators for Country i / Country j

### Baseline gravity results (regional and sub-regions)
- Baseline regressions (no policy variables or proxies for constraints) show:
  - Significant under-trading only in the case of services for Latin America and the Caribbean (LAC) as a whole (Figure 8). Note: ** statistically significant at the 5 percent level. Otherwise, not statistically significant.
- Disaggregated findings:
  - Intra-regional trade in LAC is lower compared to what would be predicted by economic and geographic factors (Table 3).
    - Merchandise trade: coefficient for extra-regional trade negative but not statistically significant; intra-regional trade negative and statistically significant.
    - Services: substantial under-trading both with extra- and intra-regional partners, with more pronounced under-trading intra-regionally.
  - Sub-region differences (Figure 9):
    - South America: significant under-trading in manufactured goods and services.
    - Caribbean: significant under-trading across all product groups (merchandise trade, manufacturing, primary commodities, and services).
    - Central America: trade flows below gravity benchmark in merchandise goods (both manufactured goods and primary commodities), but not in services.
    - Mexico: baseline regressions suggest significant over-trading in manufactured goods.

### Benchmarking constraints (summary of Figure 10)
- Values are averages for the period 2015-2019. MFN tariffs are rates, MATR is a count of restrictions, the LPI is an index, and constraints are share of firms identifying each factor as a constraint.
- LAC median compared to EMDE (excluding LAC) 25th and 75th percentiles:
  - In most cases LAC countries stand between best and worst performers in EMDEs, indicating scope for improvement.
  - MATR: median LAC country stands close to the best performers among non-LAC EMDEs (relatively low non-tariff restrictions).
  - Electricity as a constraint and governance as a constraint: median LAC country stands closer to the worst performers among EMDEs (indicating disproportionate negative effects).

### Augmented gravity regressions — how constraint sets affect sub-regions
- Method: Augment baseline gravity with four sets of variables — trade policy; transport infrastructure and customs regulations; access to and quality of factor inputs; governance indicators. Results summarized in Figures 11–14 and Tables 4–13.

- South America (Figure 11):
  - Trade policy variables: negligible impact on regional dummy coefficients.
  - Transport infrastructure and customs (LPI): regional dummy coefficient halves for manufactured goods but significant under-trading remains; under-trading in services fully explained by LPI.
  - Addition of digital infrastructure (mobile broadband users per 100 inhabitants): marginal impact.
  - Factor inputs (WBES electricity and access to finance, plus HCI): notable reduction in regional dummy for manufacturing (not services).
  - WBES governance average (political instability, corruption, theft/crime): inclusion makes coefficients on regional dummies statistically insignificant across all product groups.

- Central America (Figure 12):
  - Trade policy variables and WBES governance: little impact; regional dummies continue to show significant under-trading for manufactured goods and primary commodities.
  - LPI index, particularly transport infrastructure: notably reduces regional dummy for manufacturing but under-trading remains significant; marginal impact on primary commodities.
  - Human Capital Index and WBES electricity/access to finance: little impact on regional dummy values despite many factor variables being statistically significant and of expected sign.

- Mexico (Figure 13):
  - Trade policy variables: fully explain over-trading in merchandise trade (manufactured goods).
  - Addition of NAFTA dummy: implies significant under-trading in primary commodities (possibly reflecting NAFTA favoring manufactured goods over primary commodities).
  - WBES governance average: reduces extent of under-trading in primary commodities somewhat.

- Caribbean (Figure 14):
  - Trade policy variables and factor input variables: do not explain under-trading in merchandise trade or services.
  - WBES governance variables: do not explain under-trading.
  - LPI transport and customs variables: regional dummy for merchandise trade becomes statistically insignificant (i.e., helps explain under-trading in manufactured goods), but no notable impact on services.

### Robustness checks
- Replacements in robustness checks:
  - Replace World Bank LPI index variables with WBES transport and customs survey results (Table 14).
  - Replace Human Capital Index with WBES inadequately educated workforce survey result (Table 15).
  - Replace WBES governance indicators with WGI governance indicators (Table 16).
- Robustness outcomes:
  - Results generally less satisfactory with alternative variables.
  - South America:
    - WBES transport and customs variables fully explain under-trading in manufacturing but negligible impact for services.
    - WBES inadequately educated workforce variable shows statistically significant sign opposite to expectations for South America.
    - WGI governance indicators help explain some under-trading in services, but not in merchandise trade.
  - Central America and Caribbean:
    - WBES transport and customs variables have marginal impacts.
    - WBES inadequately educated workforce variable shows no notable impact on regional dummies.
    - WGI governance indicators do not explain under-trading.

### Key empirical conclusions (Section VII)
- Baseline regressions (no policy/constraint variables): significant evidence of under-trading in LAC only for services.
- Disaggregation by sub-region reveals broader under-trading:
  - South America: significant under-trading in merchandise goods (particularly manufacturing) and services.
  - Caribbean: significant under-trading across all product groups (merchandise trade and services).
  - Central America: significant under-trading in merchandise goods (manufactured goods and primary commodities), but not services.
  - Mexico: significant over-trading in manufactured goods (baseline).
- LAC’s under-performance in trade primarily emanates from intra-regional trade rather than inter-regional trade.
- Constraint variables explain parts of under-trading:
  - Poor transport infrastructure and inefficiencies in customs clearance (LPI transport and customs variables) explain a significant part of under-trading in manufactured goods for South America and the Caribbean.
  - WBES governance indicators significant in explaining under-trading in manufactured goods and services for South America, but not for Central America or the Caribbean.
  - Access to factor inputs cannot fully explain under-trading for any sub-region, though HCI reduces under-trading in manufactured goods for South America.
  - For Mexico, trade policy variables fully explain over-trading in manufactured goods; NAFTA dummy introduction implies significant under-trading in primary commodities (possible resource re-allocation effect).
- Research gaps identified:
  - Further research needed to understand (i) factors underpinning Central America’s and the Caribbean’s underperformance in trade, and (ii) the benefits of removing constraints behind LAC’s trade underperformance.

*Source: wpiea2024032-print-pdf - Box 1: Gravity Model: Explanation of Variables (cont.)*

### Annex I. Tables of gravity model results

### Annex I. Tables of gravity model results

### Table 1. Baseline gravity model regressions - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Key coefficients (coef; tstat):
  - LGDPi: 0.778***; 18.86 | 0.770***; 19.72 | 1.048***; 29.33 | 1.046***; 29.50
  - LGDPj: 0.813***; 14.36 | 0.803***; 15.33 | 1.065***; 36.81 | 1.063***; 36.65
  - LPOPi: -0.00525; -0.103 | -0.00619; -0.125 | -0.370***; -8.670 | -0.369***; -8.661
  - LPOPj: -0.126***; -2.595 | -0.125***; -2.705 | -0.369***; -10.65 | -0.368***; -10.67
  - LDISTANCE: -0.427***; -7.066 | -0.426***; -7.193 | -0.597***; -19.20 | -0.596***; -19.26
  - LANG: 0.290***; 2.739 | 0.327***; 3.308 | 0.835***; 10.09 | 0.841***; 10.21
  - BORDER: 1.159***; 7.006 | 1.098***; 7.462 | -0.0285; -0.232 | -0.0330; -0.273
  - LANDLLi: -0.134; -1.238 | -0.144; -1.321 | -0.284**; -2.445 | -0.286**; -2.462
  - LANDLLj: -0.283***; -2.593 | -0.287***; -2.647 | -0.167; -1.301 | -0.168; -1.307
- Observations: 21,010 | 21,010 | 13,687 | 13,687
- R-squared: 0.456 | 0.495 | 0.751 | 0.752
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 2. Baseline gravity model regressions - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij
- Key coefficients (coef; tstat):
  - LGDPi: 0.814***; 17.35 | 0.806***; 18.05 | 0.610***; 13.34 | 0.600***; 13.31
  - LGDPj: 0.855***; 12.60 | 0.843***; 13.55 | 0.624***; 13.71 | 0.623***; 13.57
  - LPOPi: 0.0159; 0.279 | 0.0150; 0.269 | -0.0979*; -1.828 | -0.0991*; -1.869
  - LPOPj: -0.181***; -3.246 | -0.180***; -3.405 | 0.133**; 2.276 | 0.132**; 2.264
  - LDISTANCE: -0.444***; -6.823 | -0.442***; -6.939 | -0.359***; -5.895 | -0.364***; -6.070
  - LANG: 0.291**; 2.424 | 0.334***; 3.008 | 0.213; 1.493 | 0.234*; 1.650
  - BORDER: 1.154***; 6.442 | 1.079***; 6.829 | 1.190***; 6.360 | 1.176***; 6.442
  - LANDLLi: 0.0312; 0.255 | 0.0256; 0.210 | -0.911***; -5.637 | -0.946***; -5.882
  - LANDLLj: -0.235**; -1.987 | -0.238**; -2.021 | -0.751***; -5.316 | -0.760***; -5.374
- Observations: 21,010 (all columns)
- R-squared: 0.418 | 0.459 | 0.265 | 0.271
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 3. Gauging Intra-regional Trade: Baseline regressions - Merchandise and Services
- Dependent variables: LTrMRCij, LTrSERVij
- Selected coefficients (coef; tstat):
  - LGDPi: 0.775***; 18.71 | 1.045***; 29.33
  - LGDPj: 0.810***; 14.34 | 1.061***; 36.23
  - LPOPi: -0.00271; -0.0535 | -0.367***; -8.624
  - LPOPj: -0.123**; -2.539 | -0.366***; -10.54
  - LDISTANCE: -0.431***; -7.096 | -0.600***; -19.07
  - LANG: 0.301***; 2.842 | 0.847***; 10.10
  - BORDER: 1.158***; 7.030 | -0.0321; -0.262
  - intra-LAC: -0.426**; -1.991 | -0.521***; -3.149
  - LANDLLi and j: see coefficients for significance in each column
- Observations: 21,010 | 13,687
- R-squared: 0.459 | 0.751
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 4. Gravity model regressions with Trade Policy Variables - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Additional trade-policy variables included: RTA, TRIj, MFNTj
- Selected coefficients (coef; tstat):
  - RTA: 0.662***; 6.793 | 0.0474; 0.560
  - TRIj: -0.292*; -1.671 | -0.0413; -0.385
  - MFNTj: -0.0393**; -1.972 | -0.0320*; -1.843
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and t-stats reported with significance levels (see table)
- Observations: 21,010 (both columns)
- R-squared: 0.495 | 0.555
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 5. Gravity model regressions with Trade Policy Variables - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij
- Selected coefficients (coef; tstat):
  - RTA: 0.756***; 7.125 | 0.286; 1.627
  - TRIj: -0.412**; -2.043 | 0.186; 0.913
  - MFNTj: -0.0410*; -1.862 | -0.0348; -1.261
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients provided with exact numeric values and significance
- Observations: 21,010 (all columns)
- R-squared: 0.459 | 0.523 | 0.271 | 0.281
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 6. Gravity model regressions with Trade Policy Variables and NAFTA - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij (four columns with NAFTA)
- Selected coefficients (coef; tstat):
  - NAFTA: 0.0258; 0.120 | 1.142***; 4.436 (reported in specific columns)
  - RTA: 0.756***; 7.125 | 0.755***; 7.114
  - TRIj and MFNTj: coefficients and t-stats provided
  - LGDPi and LGDPj: coefficients range (e.g., LGDPi 0.800***; 18.96 ... 0.575***; 13.47)
- Observations: 21,010 (all columns)
- R-squared: 0.523 | 0.524 | 0.281 | 0.377
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 7. Gravity model regressions with Transport and Customs Variables - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Transport and customs variables included: LPITRANSi, LPITRANSj, LPICUSTi, LPICUSTj
- Selected coefficients (coef; tstat):
  - LPITRANSi: 3.602***; 3.666 | -2.225***; -3.466 (in different columns)
  - LPITRANSj: 2.292**; 2.533 | -1.398*; -1.690
  - LPICUSTi: -1.501**; -2.237 | 2.748***; 5.451
  - LPICUSTj: -0.571; -0.811 | 1.312**; 2.010
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients provided with exact values
- Observations: 15,453 | 15,453 | 11,389 | 11,389
- R-squared: 0.557 | 0.618 | 0.751 | 0.754
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 8. Gravity model regressions with Transport and Customs Variables - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij
- Selected coefficients (coef; tstat):
  - LPITRANSi: 4.453***; 3.809 | 0.358; 0.383
  - LPITRANSj: 2.048**; 2.178 | 3.330**; 2.425
  - LPICUSTi: -0.0688; -0.0856 | -5.203***; -6.913
  - LPICUSTj: -0.763; -1.018 | 0.703; 0.641
  - MBUSERSi and MBUSERSj: coefficients included in some columns (e.g., MBUSERSi 0.00287*; 1.648)
- Observations: 15,453 (all columns)
- R-squared: 0.525 | 0.625 | 0.292 | 0.347
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 9. Gravity model regressions with Transport and Customs Variables and Digital Infrastructure - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Digital and infrastructure variables included: BESFINi, BESFINj, HCIi, BESELECi, BESELECj
- Selected coefficients (coef; tstat):
  - BESFINi: 0.00263; 0.511 | -0.00413; -1.221
  - BESFINj: 0.00413; 1.124 | 0.00866**; 2.551
  - HCIi: 0.483***; 3.730 | -0.401***; -4.272
  - BESELECi: -0.00807***; -3.212 | -0.00154; -0.680
  - BESELECj: -0.00248; -1.042 | -0.00772***; -2.779
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and significance reported
- Observations: 10,350 | 10,350 | 8,501 | 8,501
- R-squared: 0.509 | 0.520 | 0.714 | 0.716
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 10. Gravity model regressions with Factor Input Variables - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Factor-input and infrastructure variables included: BESFIN, HCI, BESELEC (various columns)
- Selected coefficients (coef; tstat):
  - BESFINi: -0.0180***; -3.711 | 0.0397***; 5.806 (in different columns)
  - HCIi: 0.435***; 4.020 | 0.702**; 2.053
  - BESELECi: -0.00578**; -2.300 | -0.00984**; -2.184
  - BESELECj: -0.000336; -0.134 | -0.0129***; -3.053
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and t-stats reported with exact values
- Observations: 10,350 (all columns)
- R-squared: 0.553 | 0.564 | 0.163 | 0.289
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 11. Gravity model regressions with Factor Input Variables - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij
- Selected coefficients (coef; tstat):
  - BESGOVAvg i and j: coefficients reported (e.g., BESGOVAvg i -0.00873***; -2.988)
  - LGDPi and LGDPj: coefficients in range (e.g., LGDPi 0.859***; 24.20 ... 0.968***; 31.47)
  - LDISTANCE: -0.313***; -3.204 | -0.337***; -3.212 | -0.673***; -12.94 | -0.685***; -12.42
  - CA, CAR, SA, MEX: region dummies coefficients reported
- Observations: 12,638 | 12,638 | 9,704 | 9,704
- R-squared: 0.508 | 0.499 | 0.713 | 0.708
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 12. Gravity model regressions with Governance Indicators - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Governance variables included (BESGOVAvg i/j)
- Selected coefficients (coef; tstat):
  - BESGOVAvg i: -0.0157***; -6.370 | 0.00851*; 1.907 (different columns)
  - BESGOVAvg j: -0.000103; -0.0406 | -0.0144***; -2.967
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and t-stats provided
- Observations: 12,638 (all columns)
- R-squared: 0.552 | 0.558 | 0.156 | 0.191
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 13. Gravity model regressions with Governance Indicators - Manufacturing and Primary Commodities Trade
- Dependent variables: LTrMANUij, LTrPRIPDij
- Selected coefficients (coef; tstat):
  - BESTRANSi and j, BESCUSTi and j included in robustness specifications
  - BESTRANSi: -0.0161***; -3.167 | -0.00484; -1.047
  - BESCUSTj: -0.00519; -0.685 | 0.0260***; 2.642
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and t-stats recorded in table
- Observations: 12,870 | 12,870 | 9,900 | 9,900
- R-squared: 0.507 | 0.504 | 0.713 | 0.709
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 14. Robustness regressions with Transport and Customs Variables - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Robustness variables included: BESFIN, BESSKLAB, BESELEC, etc.
- Selected coefficients (coef; tstat):
  - BESSKLABi: 0.0118***; 3.145 | -0.00383; -1.211
  - BESFINj: 0.00470; 1.293 | 0.00908***; 2.724
  - BESELECi: -0.0150***; -5.326 | 0.00111; 0.418 (in different columns)
  - BESELECj: -0.00290; -1.263 | -0.00774***; -2.798
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER: coefficients and t-stats provided
- Observations: 12,870 | 12,870 | 9,900 | 9,900
- R-squared: 0.507 | 0.521 | 0.713 | 0.711
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 15. Robustness regressions with Factor Input Variables - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Robustness variables included: WGIGOVAvg, etc.
- Selected coefficients (coef; tstat):
  - WGIGOVAvgi: 0.0246; 0.454 | 0.110**; 2.399 (in different columns)
  - WGIGOVAvgj: 0.102*; 1.849 | 0.0877*; 1.787
  - LGDPi, LGDPj, LDISTANCE, LANG, BORDER, LANDLL: coefficients and t-stats provided
- Observations: 20,460 | 20,460 | 13,687 | 13,687
- R-squared: 0.556 | 0.557 | 0.752 | 0.749
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

### Table 16. Robustness regressions with Governance Indicators - Merchandise and Services Trade
- Dependent variables: LTrMRCij, LTrSERVij
- Robustness specifications revisiting governance indicators with alternative controls
- Selected coefficients and model fit:
  - LGDPi: 0.764***; 20.99 | 0.742***; 11.08 | 1.047***; 29.66 | 0.938***; 15.31
  - LGDPj: 0.637***; 11.26 | 0.544***; 7.05 | 1.001***; 18.33 | 0.916***; 13.58
  - LDISTANCE: -0.348***; -5.460 | -0.350***; -5.556 | -0.582***; -13.86 | -0.586***; -13.82
  - LANG, BORDER, RTA, TRIj, MFNTj, regional dummies (SA, CA, MEX, CAR), LANDLL, WGIGOVAvg: coefficients and exact t-statistics reported
- Observations: 20,460 | 20,460 | 13,687 | 13,687
- R-squared: 0.556 | 0.557 | 0.752 | 0.749
- Note: t-statistics calculated using robust standard errors. *** p<0.01, ** p<0.05, * p<0.1.

*Source: Authors' calculations.*

### References

### References (wpiea2024032-print-pdf)

### Core empirical and methodological sources on gravity and trade estimation
- Baldwin, R. and D. Taglioni (2006), “Gravity for Dummies and Dummies for Gravity Equations,” NBER Working Paper 12516.
- Santos Silva, J.M.C, and S. Tenreyro (2006), “The log of Gravity,” The Review of Economics and Statistics, Vol. 88 (4): 641-658.
- Santos Silva, J.M.C, and S. Tenreyro (2011), “Further simulation evidence on the performance of the Poisson pseudo-maximum likelihood estimator,” Economics Letters, Vol. 112 (2): 220-222.
- Felbermayr, G., and Y. Yotov (2021), “From Theory to Policy with Gravitas: A Solution to the Mystery of the Excess Trade Balances”, European Economic Review, Vol. 139:103875.
- Conte, M. P. Cotterlaz and T. Mayer, 2022. "The CEPII Gravity Database," Working Papers 2022-05, CEPII research center

### Trade costs, logistics, and transport in Latin America and the Caribbean (LAC)
- Behar, A., P. Manners, and B.D. Nelson (2013), “Exports and International Logistics”, Oxford Bulletin of Economics and Statistics, Vol. 75 Issue 6, December 2013.
- Moreira, M.M., J. Blyde, C. Vulpe, and (2013, eds.), “Too Far to Export: Domestic Transport Costs and Regional Export Disparities in Latin America and the Caribbean”, Inter-American Development Bank, Washington, D.C., U.S.A.
- Moreira, M.M., C. Vulpe, and J. Blyde (2008), “Unclogging the Arteries: The Impact of Transport Costs on Latin American and Caribbean Trade”, Inter-American Development Bank, Washington, D.C., U.S.A.
- Kahn, T., A. Estevadeordal, and M. M. Moreira (2015), “Bringing Down the Barriers: A Review of IDB Research on Trade Costs in Latin American and the Caribbean”, Inter-American Development Bank, Washington, D.C., U.S.A.
- Moreira, M.M., J. Blyde, C. Vulpe, and (2013, eds.), “Too Far to Export: Domestic Transport Costs and Regional Export Disparities in Latin America and the Caribbean”, Inter-American Development Bank, Washington, D.C., U.S.A. (duplicate entry as in source)

### Trade integration, policy, and regional analysis for Latin America and the Caribbean
- Bown, C.P., D. Lederman, S. Pienknagura and R. Robertson (2017), “Better Neighbors: Toward a Renewal of Economic Integration in Latin America”, The World Bank Group, Washington, D.C., U.S.A.
- Cerra, V. et al. (2017), “Cluster Report – Trade Integration in Latin America and the Caribbean”, IMF Country Report No. 17/66, March 2017, International Monetary Fund, Washington, D.C., U.S.A.
- International Monetary Fund (October 2015), Regional Economic Outlook, Western Hemisphere Department, “Trade Integration in Latin America and the Caribbean: Hype, Hope, and Reality”, International Monetary Fund, Washington, D.C., U.S.A.
- Mowatt, R. (2017) “Trade Policy Issues in Latin America and the Caribbean: Views from Country Authorities and Current State of Play”, unpublished background paper, International Monetary Fund, Washington, D.C., U.S.A.
- Salinas, G. (2021) “Proximity and Horizontal Policies: The Backbone of Export Diversification and Complexity,” IMF Working Paper No. 2021/064.
- Campos, R., S. Pienknagura, and J. Timini (2023), “How Far has Globalization Gone? A Tale of Two Regions,” IMF Working Paper WP/23/255.

### Measurement of trade restrictions and services trade databases
- Estefania-Flores J., D. Furceri, S.A. Hannan, J.D. Ostry, and A.K. Rose (2022), “A Measurement of Aggregate Trade Restrictions and their Economic Effects”, IMF Working Paper No. 2022/001.
- Liberatore, A., and S. Wettstein (2021), “THE OECD-WTO BALANCED TRADE IN SERVICES DATABASE (BaTIS)”: https://www.oecd.org/sdd/its/OECD-WTO-Balanced-Trade-in-Services-database-methodology-BPM6.pdf

### Document identifiers and internal labels observed in the source
- IMF WORKING PAPERS Constraint on Trade on the LAC Region
- INTERNATIONAL MONETARY FUND 40

*References list as provided in wpiea2024032-print-pdf - References*

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_Source: https://www.imf.org/-/media/files/publications/wp/2024/english/wpiea2024032-print-pdf.pdf_
