Reading the Capability Map

A Handbook for SHAP–RCA Gap Analysis — Model Implications for Industrial Strategy

Author

Net Zero Industrial Policy Lab (NZIPL) · Johns Hopkins SAIS

Published

June 25, 2026

What this is. A working handbook for reading the two model-driven panels of the Atlas of the Clean Industrial Base — the Capability Radar and the PC Scatter — and turning them into industrial-strategy calls. It explains the one idea both panels encode (a gap between what a technology needs and what a country has), the seven-cell grid that names every gap, and a worked example for each cell drawn from live model output (RCA reference year 2024).

1 How to use this handbook

Read §2–3 once to learn the framework, then treat §4 as a reference: each of the seven cells has a plain-language meaning, a reading rule, a policy orientation, and a real worked case. §5 walks a full country read end to end. §6 covers what the map does not say — the limits matter as much as the signal.

The framework is deliberately coarse. It classifies clusters of capability, not individual products. As the underlying working paper puts it: precision beyond the cluster level “would be applying a false level of precision to the model.” The handbook is a guide to reasoning, not a recipe.

2 The two questions behind every panel

Both panels answer two questions at once and plot one against the other.

What does the technology need? — the SHAP weight. The competitiveness model (a Random Forest predicting whether a country reaches RCA > 1 in a clean technology) tells us which capabilities carry the predictive signal. Aggregating the model’s SHAP importances to five capability clusters — Chemicals, Electronics, Industrial Materials, Machinery, Metals — gives a weight \(w_c\) (% of the technology’s total importance) for each cluster. High weight = the model says this capability is decisive for the technology.

What does the country have? — the RCA. Revealed Comparative Advantage measures whether a country exports more of a cluster than its fair world share. \(RCA \geq 1\) means genuine specialisation; below 1 means no revealed strength. RCA is already normalised for country size and world trade, so it is comparable across countries.

Panel SHAP weight (need) Country RCA (have) Granularity
Capability Radar gold polygon, 5 axes green polygon, 5 axes Category (5 clusters)
PC Scatter x-axis y-axis (bubble = trade value) Product (HS6)

The radar and the scatter are the same comparison at two zoom levels. The radar averages each cluster; the scatter shows the individual products inside it. This distinction is not cosmetic — it is the single most common source of misreading (§4.1).

3 The gap framework: a seven-cell grid

Crossing three SHAP levels with three RCA levels yields a 3×3 grid that collapses to seven policy-relevant cells.

SHAP level (what the technology needs)

Level Threshold Meaning
High \(w_c \geq 25\%\) Critical driver — dominates the model’s signal
Medium \(10\% \leq w_c < 25\%\) Important contributor
Low \(w_c < 10\%\) Supporting role only

RCA level (what the country has)

Level Threshold Meaning
Strength \(r_c \geq 1.0\) Genuine specialisation
Partial \(0.5 \leq r_c < 1.0\) Approaching competitiveness
Weak \(r_c < 0.5\) No meaningful specialisation

The grid

Strength \(r\geq1\) Partial \(0.5\leq r<1\) Weak \(r<0.5\)
High SHAP \(\geq25\%\) 🟢 Leverage 🟠 Build-up 🔴 Critical gap
Medium SHAP 10–25% 🟡 Mature strength 🟠 Build-up 🟥 Gap
Low SHAP \(<10\%\) 🔵 Bonus strength Not a priority Not a priority

The diagonal logic is the whole point: the top-left is where a country’s strength meets the technology’s need (act here first), and the top-right is where the technology’s most important need is unmet (the hardest, most strategic problem).

4 The seven cells, with worked examples

Each cell below pairs the reading rule with a real case from model output (reference year 2024). The three “hero” cases you will see recur — India · Solar, Brazil · Biofuel, Canada · Batteries — because a single country×technology typically spans several cells across its five clusters. That is normal and is exactly how the map is meant to be read.

4.1 A note before the cells: radar vs. scatter

Brazil · Biofuel — capability radar (category level)
Category SHAP % RCA Classification
Machinery 33.5 0.47 Critical gap
Chemicals 30.3 0.19 Critical gap
Industrial Materials 25.1 0.92 Build-up
Metals 11.1 0.55 Build-up

On the radar, Brazil · Biofuel shows no Leverage cell — its high-need clusters (Machinery, Chemicals) sit in Build-up / Critical gap. Yet on the PC scatter, Brazil holds clear Leverage products: sugarcane-derived ethanol and processing inputs where its product-level RCA is far above 1 and the model weights the product heavily. Both readings are correct. The category average dilutes a handful of star products; the scatter resolves them. Rule: use the radar to set the strategic frame, the scatter to find the specific products to anchor.

4.2 🟢 Leverage — strength meets need

Reading rule: High SHAP (\(\geq25\%\)) and RCA \(\geq 1\). The country already specialises in a capability the technology most demands.

Policy orientation: Anchor FDI and supply-chain strategy here. This is the nucleus to build outward from — the country competes where it counts.

Worked case — Brazil · Biofuel (product level). Brazil’s sugarcane-ethanol complex is the textbook leverage position: the feedstock-processing products the biofuel model weights most are exactly the ones Brazil dominates in world trade. On the scatter these bubbles sit top-right; the radar’s Metals/Industrial-Materials clusters carry the diluted signal of the same strength.

4.3 🟠 Build-up — close enough to matter

Reading rule: High or Medium SHAP and Partial RCA (\(0.5 \leq r < 1\)). The country is just below the competitiveness line in an important capability.

Policy orientation: Highest expected return on targeted investment. A modest push to cross \(RCA = 1\) converts a near-miss into a genuine strength.

Worked case — Canada · Batteries.

Canada · Batteries — capability radar (category level)
Category SHAP % RCA Classification
Chemicals 48.6 0.94 Build-up
Machinery 32.9 0.53 Build-up
Metals 9.5 0.49 Not a priority
Electronics 6.0 0.37 Not a priority
Industrial Materials 2.9 0.00 Not a priority

Canada’s two highest-need battery clusters — Chemicals and Machinery — sit in Build-up (RCA just under 1). With strong upstream minerals and existing chemical capacity, this is a country one targeted step from competitiveness in the capabilities batteries most reward.

4.4 🔴 Critical gap — the top driver is missing

Reading rule: High SHAP (\(\geq25\%\)) and Weak RCA (\(r < 0.5\)). The model’s single most important capability is absent.

Policy orientation: The hardest problem. Requires upstream industrial policy — sector-building, not just incentives. Cannot be closed by demand subsidies alone.

Worked case — India · Solar.

India · Solar — capability radar (category level)
Category SHAP % RCA Classification
Chemicals 38.9 0.50 Critical gap
Metals 23.7 0.91 Build-up
Electronics 22.7 0.17 Gap
Machinery 12.0 0.72 Build-up
Industrial Materials 2.7 0.24 Not a priority

India assembles modules competitively but the model’s top-weighted cluster for solar — Chemicals (the polysilicon / cell-chemistry layer) — sits in Critical gap. This is the well-known “deep upstream” vulnerability: strong at the visible end of the chain, absent where the model says competitiveness is actually decided.

4.5 🟡 Mature strength — real but not decisive

Reading rule: Medium SHAP (10–25%) and RCA \(\geq 1\). A genuine supporting capability in a cluster of secondary importance.

Policy orientation: Maintain and deepen. Useful, but not enough on its own to carry a technology strategy.

Worked case — Canada · Nuclear. The Chemicals cluster (SHAP 22%, RCA 5.71) is a maintained specialisation that supports, but does not by itself decide, competitiveness in this technology.

4.6 🟥 Gap — a secondary driver missing

Reading rule: Medium SHAP (10–25%) and Weak RCA (\(r < 0.5\)). An important-but-not-critical capability is absent.

Policy orientation: Worth addressing, but not a show-stopper alone. Sequence it after the critical gaps.

Worked case — India · Solar · Electronics. Alongside its Chemicals critical gap, India’s Electronics cluster for solar sits in Gap — a real but second-order weakness (inverters, power electronics) to address once the upstream chemistry is underway.

4.7 🔵 Bonus strength — strength the tech doesn’t reward

Reading rule: Low SHAP (\(<25%\) — under 10%) and RCA \(\geq 1\). A genuine capability in a cluster this technology weights lightly.

Policy orientation: Do not anchor tech-specific strategy here — but flag it: this strength may be decisive for a different technology. A cross-technology asset.

Worked case — Brazil · Heat Pumps. A strong Chemicals position (RCA 11.71) that the Heat Pumps model weights only 4% — real capability, but better leveraged for a technology that prizes it.

4.8 ⚪ Not a priority — neither side cares

Reading rule: Low SHAP and Partial/Weak RCA. Neither the technology nor the country emphasises this cluster.

Policy orientation: Low-salience. Note and move on — strategy capacity is better spent on the actionable cells above.

Worked case — India · Solar · Industrial Materials. Low model weight, low Indian RCA: correctly ignored in a solar strategy.

5 A full read: India · Solar, end to end

Read top to bottom by need: Chemicals is the top driver and a Critical gap (the strategic priority). Metals and Machinery are Build-up — close, high-return targets. Electronics is a secondary Gap. Industrial Materials is Not a priority. One panel, a complete sequencing of where to act and in what order.

6 What the map does not say

  • Clusters, not products. A high-SHAP cluster signals what kind of capability matters, not a list of HS6 codes to build. Use the scatter to descend to products, but treat product specifics as illustration, not prescription.
  • Radar dilutes; scatter resolves. A Build-up cluster can hide a Leverage product (and vice versa). Always cross-check the two panels (§4.1).
  • Macro features are excluded from the radar. The model also learns from GDP, governance, patents and other country covariates; the radar shows only the five traded-capability clusters. A country can have a clean radar yet face non-trade barriers.
  • RCA is a revealed, lagging measure. It reflects what a country has exported, not nascent capacity. Pair with the trade-timeline and firm-activity panels for momentum.
  • Thresholds are conventions. The 25% / 10% and 1.0 / 0.5 lines are defensible but not magic. Cases near a line should be read as “between cells,” not snapped to one.

7 One-page cheat sheet

Cell Need (SHAP) Have (RCA) Do
Leverage High Strength Anchor FDI; build outward
Build-up High/Med Partial Invest — highest return; cross RCA = 1
Critical gap High Weak Sector-build upstream; hardest problem
Mature strength Med Strength Maintain and deepen
Gap Med Weak Address after critical gaps
Bonus strength Low Strength Don’t anchor here; asset for another tech
Not a priority Low Partial/Weak Note and move on

Radar = category zoom (set the frame). Scatter = product zoom (find the anchor). Reference year 2024.