Hi Roy,
If your 5-point scale is something akin to...
5-Definitely would buy
4-Probably would buy
3-Might or might not buy (= midpoint)
2-Probably would not buy
1-Definitely would not buy
...then dropping the midpoint effectively forces respondents into an either/or decision (e.g., in the above example, it reduces to "would buy" vs. "would not buy"). This is a more stringent approach and, in most marketing research cases, is generally avoided because there is usually insufficient information for respondents to provide definitive answers. For example, a respondent might legitimately struggle with a future intent question if you haven't provided adequate product, pricing, or size data. A four-point scale * may * be a superior design if you want to minimize ambiguity -- although a "don't know/not sure" response would still be advised. HTH,
Bob Walker
Surveys & Forecasts, LLC
www.safllc.com
----- Original Message -----
From: Roy FGH
Date: Monday, May 21, 2007 5:56 am
Subject: 4 level Likert scale
To:
[hidden email]
> i am conducting a motivation survey using a 4 level Likert
> scale. i found
> not many literature for this 4 level scale. can anybody give me
> literaturesfor the reason why i better use a 4 level or 5 level
> scale? thanks for
> advancing.
>
Bob Walker
Surveys & Forecasts, LLC
www.safllc.com