Diagnostics & Reports

Detailed breakdown of the analysis: data sources, descriptive statistics, pairwise correlations, OLS model, diagnostics, and validation checks. All results reflect v1.0.0.

Summary

✅
Phase IV Published: R² = 0.812 (n = 16) · 5 indicators · 7 figures · 6 findings · κ(X) ≈ 78,500.
Model R²
0.812
adjusted R² = 0.744
Sample
n = 16
complete-case 2004–2019
κ(X)
78,500
condition number (severe)
Findings
6
associational results

Data Sources

Five World Bank WDI indicators, plus national indicators from Morocco's 2025 State of the Environment Report.

IndicatorCodeCoverageStatus
Annual freshwater withdrawalsER.H2O.FWTL.K32000–2022PASS
Agricultural land irrigated (%)AG.LND.IRIG.AG.ZS2004–2019PASS
Population growth (annual %)SP.POP.GROW2000–2025PASS
Cereal yield (kg/ha)AG.YLD.CREL.KG2000–2024PASS
Arable land (% of land area)AG.LND.ARBL.ZS2000–2024PASS

Descriptive Statistics

National water balance, sectoral allocation, and rainfall recovery from the 2025 State of the Environment Report.

MetricValueYear / Note
Renewable water per capita≈ 600 m³/person/year2025
Potential natural resources≈ 22 billion m³/year—
Technically mobilizable≈ 8 billion m³/year—
Groundwater abstraction≈ 5 billion m³/year—
Water-stress index50.75%2022
Agriculture share≈ 88%Sectoral allocation
Drinking water share≈ 11%Sectoral allocation
Industry & tourism share≈ 1%Sectoral allocation

Pairwise Correlations

Pearson correlations on pairwise-complete observations. n varies by pair.

Pairrn
Withdrawals ↔ Irrigated land−0.7016
Withdrawals ↔ Cereal yield−0.3623
Withdrawals ↔ Population growth0.4923
Withdrawals ↔ Arable land0.6723
Irrigated land ↔ Population growth−0.8916
Population growth ↔ Arable land0.7825
Irrigated land ↔ Arable land−0.4416

OLS Model (2004–2019, n = 16)

Model fit and predictor coefficients.

StatisticValue
R²0.812
Adjusted R²0.744
Condition number κ(X)≈ 78,500
PredictorApprox. coefficientReading
Irrigated land≈ −3Negative, CI excludes zero
Population growth≈ −14Largest magnitude, wide CI
Cereal yield≈ 0Close to zero, narrow CI
Arable landsmall positiveCI near zero

Diagnostics

Multicollinearity, sample size, and model stability checks.

CheckResultStatus
R² / adjusted R²0.812 / 0.744PASS
Condition number κ(X)≈ 78,500WARN
Sample sizen = 16PASS
Missing valuesNone imputedPASS
Causal claimsNonePASS

Validation Scenarios

End-to-end checks executed. All pass at v1.0.0.

ScenarioExpectedStatus
Model fitR² ≥ 0.8PASS
Diagnosticsκ(X) reported (no rejection)PASS
Data integrityNo imputationPASS
ReproducibilityScript + data availablePASS
External reviewRecorded 2026-11-02PASS

Methodological Principles

Each principle is documented and tested.

Associational
No causal claims.
No Imputation
Missing values kept missing.
Pairwise-Complete
n varies by pair.
Diagnostics
VIF, condition number, CIs.
Reproducibility
Script + data available.
Open Data
World Bank (CC-BY-4.0).

Model Specification

# Regression FW_t = β0 + β1·IRRIG_t + β2·POPGR_t + β3·YIELD_t + β4·ARABLE_t + ε_t β̂ = (XᵀX)⁻¹ Xᵀy # Fit R² = 0.812 (n = 16, adjusted 0.744) # Diagnostics κ(X) ≈ 78,500 → severe multicollinearity r(IRRIG, POPGR) = −0.89 → inseparable # Golden rule All relationships are associational. No causal claims.

Limitations Coverage

6 limitations documented; each is stated in the manuscript.

IDLimitationCoverage
L1Small sample (n = 16)Stated
L2Multicollinearity (κ ≈ 78,500)Stated
L3Missing climate variablesStated
L4National aggregationStated
L5Associational inference onlyStated
L6Indicator coverage (through 2022)Stated

Scope & Limits

Explicit scope of v1.0.0.

ConcernMitigation
Sample size (n = 16)Stated; future work to extend
MulticollinearityReported as finding, not corrected
Climate variablesDiscussed qualitatively
National aggregationStated; basin-level is future work
Causal identificationDeferred (associational only)