上述結果顯示,小型開源大型語言模型是可行的零樣本與少樣本外匯預測工具,且在未經微調的情況下,提示策略對預測表現的影響較新聞資料增強更為可靠。;Three LLMs (Llama3-8B, Mistral-7B, Qwen2.5-7B) are evaluated with the ChatTime tokenization framework on five USD currency pairs (IDR, TWD, AUD, EUR, SGD) across three horizons (1, 5, and 10 days), under a 2 x 2 factorial ablation design, against seven baselines (ARIMA, LSTM, XGBoost, iTransformer, vanilla Transformer, Naive, Moving Average). Performance is measured with RMSE, MAE, MAPE, Directional Accuracy (DA), and R^2.
LLMs outperform all baselines across every currency pair and horizon, with Qwen2.5-7B achieving the lowest mean RMSE of 27.48, compared to 91.81 for the best baseline (XGBoost). A Diebold--Mariano test confirms lower LLM loss in all 45 model-currency-horizon comparisons, significant in 38. All LLMs achieve positive mean R^2 (up to 0.50), while every baseline achieves negative mean R^2. News augmentation does not consistently improve performance, with higher RMSE observed in 32 of 45 units when news is added and the effect significant in only 11; no significant DA effect is found. Few-shot prompting reduces mean RMSE by approximately 8.2% and raises mean DA from 51.79% to 53.25% relative to zero-shot, reaching significance in 16 of 45 units. A pattern consistent with a disordinal interaction between news and prompting strategy is observed for DA, suggesting the effect of news augmentation depends on the prompting approach used.
These findings demonstrate that small open-source LLMs are viable zero-shot and few-shot forecasters for FX markets, and that prompting strategy is a more reliable performance driver than news augmentation in the absence of fine-tuning.