本研究旨在探討盈餘組成份子預測數字之可靠性和攸關性。可靠性係探討預測準確度，而攸關性探討預測資訊發佈時市場之反應。一般而言，會計資訊分為「財務報表」資訊與「財務預測」資訊兩種，鑑於過去研究多在探討盈餘組成份子帳面數字之攸關性，尚未有文獻探討盈餘組成份子預測數字之攸關性，及檢定其預測數字是否同時兼具可靠性與攸關性。故，本研究分析盈餘組成份子預測數字之相對可靠性與攸關性後，再將樣本依可靠性分群，觀察可靠性高低是否會影響盈餘及其組成份子預測數字之攸關性。此外，另檢測盈餘組成份子帳面數字之攸關性，以比較兩種會計資訊之攸關性。 在可靠性方面之實證結果顯示，盈餘組成份子預測數字可靠性不同，最高為營業收入，最低為稅後盈餘；在攸關性方面之實證結果顯示，僅分析稅後盈餘預測數字時，稅後盈餘係具有攸關性；但加入其他盈餘組成份子同時分析時，營業淨利與稅後盈餘皆具有攸關性，而營業收入則無攸關性。此外，盈餘組成份子帳面數字之攸關性順序則為營業淨利大於稅後盈餘及營業收入，此結果亦顯示投資者對帳面數字之資訊較為重視。 另外，可靠性對攸關性影響之實證結果顯示，預測資訊之可靠性不同時，其盈餘及其組成份子預測數字之攸關性亦不同；預測資訊可靠性低時，其預測資訊之攸關性較高；且其盈餘組成份子中，只有稅後盈餘具有攸關性。基此，本研究認為預測資訊之可靠性會影響盈餘及其組成份子之攸關性。整體而言，在盈餘組成份子預測數字中，投資者主要關切的資訊為營業淨利及稅後盈餘。 This paper studies the reliability and relevance of earnings components forecasting numbers released by listed companies in the Taiwan Stock Exchange. The reliability is measured by forecast accuracy, and the relevance is measured by market response when company release earnings forecasting information. The empirical results show that, in aspect of reliability, the reliability of earnings components forecasting numbers are significantly different, the highest one is sales revenue, and the lowest one is income after tax. In aspect of relevance, forecasting number of income after tax is relevant. However, after adding other earnings components into analysis, operating income and income after tax have relevance. Moreover, in earnings components accounting numbers, operating income is more relevant than income after tax and sales revenue. Besides, the income after tax in the group with low reliability is more relevant. And then probe into earnings components further in the group with low reliability, only income after tax has relevance. Therefore, the conclusion indicates that the reliability of earnings forecast can influence the relevance of earnings forecast and earnings components. Generally, investors concern about operating income and income after tax when they get earnings forecasting information.
