2009年4月4日星期六

質性研究 vs. 信度效度

1. 先從社會科學的研究過程談起。研究過程一言以蔽之大約就是胡適的那句名言:「大膽假設,小心求證」。更進一步來說,「大膽假設」指的是研究過程中「發現的脈絡」(context of discovery),研究問題的指認出、研究假說的提出、檢驗假說的程序都是在這個脈絡之中發生的。「小心求證」則點出了研究過程中「證明的脈絡」(context of justification),在這個脈絡中主要的課題是用什麼方法來檢驗假說是最恰當的。


2. 大部份研究論文中所謂「研究方法」都是在「證明的脈絡」中運作,而所謂「研究設計」的目的即是要確保用來「檢驗假說之工具」是嚴謹而客觀的。當假說通過適當的檢驗之後,研究者便回答了研究問題,研究過程也告一段落。

3. 量化研究中最普遍的「檢驗工具」便是實驗或問卷,而信度與效度則是用來評估「檢驗工具」好壞的指標。信度評估的是「檢驗工具」的可信度與精確程度,而效度則是評估「檢驗工具」所獲得的資料是否能有效地用來推論變項的特徵。

4. 質性研究的「檢驗工具」最常見的便是觀察與訪談。若硬要把量化研究中發展出來的信度與效度用來評估質性研究的「檢驗工具」,那信度或可解釋為「如何確保受訪者是真誠地回應研究者的問題」,而效度或可解釋為「受訪者的主觀經驗是否能有效地轉成可比較可分析的資料」。

5. 然而,若社會科學要窮其所能確保研究程序的客觀度,只討論信度與效度是不夠的,因為無論信效度多高,它都只在「證明的脈絡」中運作,它並不能保証「發現的脈絡」的客觀性;也就是說,研究問題的指認出、研究假說的提出是否隱含了具偏見的預設仍無從檢驗。因此就整體研究過程而言,根本就不具客觀性,信度與效度恐怕只成了無效且不可信的指標了。

6. 質性研究因而應揚棄對信效度的追求,要同時思考如何同時極大化「發現的脈絡」與「證明的脈絡」之客觀性。

7. 至於"研究"到底意謂什麼,請參考http://spaces-hope.blogspot.com/2011/02/blog-post_10.html
8. "理論"是什麼可參考http://spaces-hope.blogspot.com/2009/04/blog-post_04.html

4 則留言:

  1. I sincerely appreciate your topic related to the description and analysis of qualitative research method, which runs a bell to me. Now I am working on my thesis writing, which is required to be finished in 2 weeks. However, I do not have a very good advisor to guide me to meet the aim at analyzing the data with a correct method, which may be the qualitative research method or not. With reviewing your topic, I obtain an general idea that talked me that "I am working on a qualitative research actually." I thus start to write the chapter "Methodology" with a guidance of qualitative method. This is a good startpoint for my thesis, even though it is coming late. Anyway, the above-mentioned reflection is to let you know that your short article posed on this website is helpful for me and SAVE my thesis finally. Thank you so much.

    A graduate school, MA in English-TESL
    Arkansas Tech University
    Liang

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  2. I am very glad that my essay could have some minor contribution to your thesis. As you may see, you are the first respondent for this essay. So your response really encourages me very much. I hope we can have more interaction in the future, and wish you passing your test in a fling collar.

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  3. This is Liang again.
    I have finished "Methodology" chapter this afternoon, 24 Mar. 2010 (American date). I am about to conduct my "Data Analysis" and that will be finished in 3 days due to the time limit and the thesis dued. It seemed that you played an assistant role toward the practice of my thesis, which might be being dying or shortening in somewhere right before two days. Thank God, I found your article/or reflection; it spired me with sketching a blueprint of methods in my mind that originally shoud be filled with a simple "project", not a thesis.
    Again, thank you soooooo much. I will complete my degree in the coming June, 2010, and I'll get back to Taiwan, continuing my teaching job in high school, yet to be a professor is my ultimate goal now in that I found I am being loveing in the teaching career as a professor. Thus, I'm going to apply for a further degree for my PhD program in u.s.a., and then I can get a teaching job in Taiwan's colleges or universities. In point of this reason, the thesis will be VERY important for me, for my future.
    Anyway, as an English teacher in Taiwan and a graduate student in USA, I believed that your blog provided many students no matter inside or outside your classes with a mass of help, which is much better than any other teachers in Taiwan. Unfortunately, most of them regard the instruction as a tool to earn their living, and ignore a teacher's position on a facilitator to build up the bridge between knowledge and learning for their students. You are very worth being a teacher in Taiwan. Admire you.
    Have a nice day.

    Liang
    9:00 p.m. Wed. AR,USA.

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  4. Yes, I quite agree with you, Liang. This blog is sooo much helpful to me as well

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