Re: st: RE: Mean test in a Likert Scale

[Leonor Saravia <lmisaravia@gmail.com>]

Dear Nick and David,

I really appreciate your reply, thank you.

I read carefully your answers to my questions and as Nick says, my
first question pointed to the fact that there could be the sence in
which computing the mean score of a Likert scale is allowed. I have
seen practical studies were the mean of this kind of scales are
calculated and interpreted. However, there is also literature that
indicates that, as the Likert scales are an ordinal-level measure, you
should not calculate the mean of it. So, I am confused because I do
not understand whether calculating and interpreting the mean of a
Likert scale is correct or not.

The data I have is desagregated by individual (20000 observations) of
a treatment and a control group, and has the answer for each of the 26
questions, a number between 1 and 5, which are the values of a 5 point
Likert scale from Disagree (1) to Agree (5).

For instance, the first question (Q1) is: "Chilean people find
entrepreneurial activities socialy valuable" and the possible answers
are:

1 - Strongly disagree
2 - Disagree
3 - Nor agree nor disagree
4 - Agree
5 - Strongly agree

So, the database has this structure:

Observation     Group            Q1  Q2  .....  Q25  Q26
1                     Treatment      1     5   ......   3      1
2                     Control           3    1   .......  2      5
.
.
19999             Control          5     2  ........ 4       3
20000             Treatment      3     2  ......... 5      4