Forecasts for key macroeconomic variables are almost always made simultaneously by the same organizations, presented together, and used together in policy analyses and decision-makings. It is therefore important to know whether the forecasters are skillful enough to forecast the future values of those variables. Here a method for joint evaluation of skill in directional forecasts of multiple variables is introduced. The method is simple to use and does not rely on complicated assumptions required by the conventional statistical methods for measuring accuracy of directional forecast. The data on GDP growth and inflation forecasts of three organizations from Thailand, namely, the Bank of Thailand, the Fiscal Policy Office, and the Office of the National Economic and Social Development Council as well as the actual data on GDP growth and inflation of Thailand between 2001 and 2021 are employed in order to demonstrate how the method could be used to evaluate the skills of forecasters in practice. The overall results indicate that these three organizations are somewhat skillful in forecasting the direction-of-changes of GDP growth and inflation when no band and a band of +/- 1 standard deviation of the forecasted outcome are considered. However, when a band of +/- 0.5% of the forecasted outcome is introduced, the skills in forecasting the direction-of-changes of GDP growth and inflation of these three organizations are, at best, little better than intelligent guess work.

翻译：宏观经济关键变量的预测几乎总是由同一机构同时完成、共同呈现，并共同用于政策分析和决策。因此，了解这些预测者是否具备足够技能来预测这些变量的未来值至关重要。本文提出了一种用于同时评估多变量方向预测技能的方法。该方法操作简单，无需依赖传统统计方法用于衡量方向预测准确度所需的复杂假设。为展示该方法在实际中如何用于评估预测者技能，本文采用了泰国三家机构（泰国银行、财政政策办公室、国家经济与社会发展委员会）关于GDP增长和通货膨胀的预测数据，以及2001年至2021年泰国GDP增长和通货膨胀的实际数据。总体结果表明，在不设区间以及考虑预测结果±1个标准差区间时，这三家机构在预测GDP增长和通货膨胀的方向变化方面具备一定技能。然而，当引入预测结果±0.5%的区间时，这三家机构在预测GDP增长和通货膨胀方向变化方面的技能充其量仅略优于智能猜测。