數字會說話？：報紙民調報導的可信度研究
Statistic speaks? -A credibility study of poll reports

高秋萍
Kao, Chiu Ping

近幾年，媒體對重大議題以及選舉所做的民意調查報導有增加的趨勢。但是閱\聽人如何評價這些充斥媒體版面的民調報導報導可信度？民調報導可信度如何評估？
根據Weiss對於內、外部可信度的區分，民調報導可信度會受到民調來源可信度與媒介可信度的影響。本研究整理過去媒介可信度的測量，發展更全面的媒介可信度量表。內部可信度部分，則是引用美國AAPOR建議民調發佈應符合的8規範，作為評估內部可信度的標準。針對大台北地區20歲以上民眾為研究對象，並以報紙關於90立委與縣市長選舉民調報導為例。
本研究問題有二：
1.可信度的層面為何？
2.民眾對於內部來源(民調資料)可信度、外部來源(媒介)可信度與民調報導可信度的評價？
3.內、外部來源可信度如何造成民調報導可信度的差異。
研究發現
經因素分析，民調報導可信度可以歸納出「客觀性」、「專業性」與「易讀性」三個層面。媒介可信度除了上述三個層面外，還多了「真實性」層面，至於內部來源可信度，經因素分析只顯示一個因素—民調來源「知識性」。
在人口變項與可信度評價的關聯方面，學生、年輕族群、大專以上教育程度並具備隨機抽樣知識、以報紙為主要新聞來源者，對於報紙民調來源知識性的評價與民調報導的可信度評價較高。具有隨機抽樣知識與較相信報紙者，對於媒介可信度評價較高，但是教育程度愈高，對於媒介「真實性」表現愈持批判立場。
至於Weiss提出的，可信度受到內、外部來源可信度影響的論點，只有外部來源可信度的影響力獲得證實。結果顯示，閱\聽人並不會因為民調資料是否提供足夠的方法細節，而選擇是否相信報紙的民調報導。顯然他們主要是受到媒介可信度所左右，且媒介可信度的「專業性」與民調報導可信度的「專業性」評價呈現正向關聯。代表愈認同報紙專業者，對於報紙民調報導的專業性評價愈高。

In recent years, there are more and more reports about public opinion poll results in the media. The purpose of this study is to find out how does the audience evaluate the credibility of those reports, and what is the evaluation criterion?
According to Weiss ’s distinguished from the internal sources and external sources credibility, the evaluation of poll reports will influenced by the internal—poll sources and the external—media credibility.
In the external sources part, this study collects the measurement of credibility concept in several important credibility researches to develop an overall credibility scale. In the internal sources part, citing the 8 norms in disclosing poll results of the reputable poll research institution— AAPOR as the measurement standard. Research population is the citizens over 20 years old in Taipei City and Taipei County. And the study thesis is on poll reports about the 90th year Legislator Election on newspaper. These questions are:
1.What are the dimensions of credibility concept?
2.How does people evaluate the credibility of internal sources, external sources and poll reports on newspaper?
3.What is the influence of internal sources and external sources on credibility evaluation of poll reports.
Results are the following:
Regarding to factors influencing audience ’s judgements of poll sources credibility, media credibility and poll reports credibility: subjects who are student, young people(20-25 ages), at least college educated, using newspaper as the major news sources and having knowledge about random sampling tend to better estimate on poll sources knowledgeability and poll reports credibility. Subjects who have knowledge about random sampling and believe on newspaper give higher evaluation on media credibility. But subjects who are more well—educated are more criticize on the media truthfulness.
Weiss ’s argument about the internal sources ’ influencing on poll report ’s credibility is not proved here. It shows that whether the poll sources provide details of survey methods, it has nothing to do with the audience ’s judgement of poll reports credibility. It is obvisously that how do the audience judge the poll reports credibility is depending on how do the audience evaluate the media credibility. It is that subjects who more approve of newspaper expertise tend to give high price on the expertise performance of poll reports credibility.

可信度，民意調查報導，民意調查，媒介表現

credibility, public opinion poll, poll reports, media performance

2002.06.29

已授權

4A-3.pdf