EconBase
← All papers

Opening the Black Box: Nowcasting Singapore's GDP Growth and its Explainability

Luca Attolico

arXiv 1 Dec 2025 · Econometrics

arXiv:2512.02092 · PDF · DOI · OpenAlex · Extracted main text

Abstract

Timely assessment of current conditions is essential especially for small, open economies such as Singapore, where external shocks transmit rapidly to domestic activity. We develop a real-time nowcasting framework for quarterly GDP growth using a high-dimensional panel of approximately 70 indicators, encompassing economic and financial indicators over 1990Q1-2023Q2. The analysis covers penalized regressions, dimensionality-reduction methods, ensemble learning algorithms, and neural architectures, benchmarked against a Random Walk, an AR(3), and a Dynamic Factor Model. The pipeline preserves temporal ordering through an expanding-window walk-forward design with Bayesian hyperparameter optimization, and uses moving block-bootstrap procedures both to construct prediction intervals and to obtain confidence bands for feature-importance measures. It adopts model-specific and XAI-based explainability tools. A Model Confidence Set procedure identifies statistically superior learners, which are then combined through simple, weighted, and exponentially weighted schemes; the resulting time-varying weights provide an interpretable representation of model contributions. Predictive ability is assessed via Giacomini-White tests. Empirical results show that penalized regressions, dimensionality-reduction models, and GRU networks consistently outperform all benchmarks, with RMSFE reductions of roughly 40-60%; aggregation delivers further gains. Feature-attribution methods highlight industrial production, external trade, and labor-market indicators as dominant drivers of Singapore's short-run growth dynamics.

Citation extraction

232
references
743
in-text mentions
232
distinct cited
0
self-citations
64,228
main-text words

appendix boundary found by none_found · 100% of the source is main text. Read the extracted text to check this.

Most heavily cited references

The works this paper leans on most, across its whole bibliography — not restricted to papers in our corpus. Ranked by composite intensity, which combines how often a work is mentioned, how many sections mention it, and how much of that falls in the main text rather than the appendix.

ReferenceIntensityMentionsSectionsMain text
1Zou, Hui and Hastie, Trevor (2005) Regularization and variable selection via the elastic net1.000125100%
2Smeekes, Stephan and Wijler, Evie (2018) Macroeconomic forecasting using penalized regression methods1.000124100%
3Akiba, Takuya and Sano, Shotaro and Yanase, Takahiko and Ohta, Taker… (2019) Optuna: A next-generation hyperparameter optimization framework1.000123100%
4Bergstra, James and Bardenet, Rémi and Bengio, Yoshua and Kégl, Balázs (2011) Algorithms for hyper-parameter optimization1.000123100%
5Hansen, Peter R. and Lunde, Asger and Nason, James M (2011) The model confidence set1.000115100%
6Breiman, Leo (2001) Random Forests1.000114100%
7Tashman, Leonard J (2000) Out-of-sample tests of forecasting accuracy: An analysis and review1.000114100%
8Bańbura, Marta and Rünstler, Gerhard (2011) A look into the factor model black box: Publication lags and the role of hard and soft data in forecasting GDP1.000104100%
9Timmermann, Allan G (2006) Forecast combinations1.000104100%
10Hewamalage, Hansika and Bergmeir, Christoph and Bandara, Kasun (2021) Recurrent neural networks for time series forecasting: Current status and future directions1.00096100%

Showing the top 10 of 232 scored citations.