Shoko, what a puzzling task you face,
with no information to guide you.
For what it's worth, to me,
"medium-low level" hints at a three-level
ranking (high, medium, low), in which
each of those levels (degree of prejudice)
is further divided into three sub-levels.
The scale that comes to mind is:
Level of prejudice Economic class (rich to poor)
(high, medium, low) (upper, middle, lower)
high-high level upper upper class (the richest 1/9)
medium-high level middle upper class
low-high level lower upper class
high-medium level upper middle class
medium-medium level middle middle class
low-medium level lower middle class
high-low level upper lower class
medium-low level middle lower class
low-low level lower lower class (the poorest 11.1%)
This is my guess.
The short answer to your questions is:
We don't know (because the writer
didn't tell us).
The writer probably knows exactly
what the ranking scale is. If only
he would let the reader see the
bureaucratic document that defines
these nine levels (or however many
levels there are), the translator's job
would be easier.
A similar ranking might be devised
for the brightness of colors (e.g.,
bright red, medium-bright green,
dark-dark yellow).
-- Mark Spahn (West Seneca, NY)