To better represent the various actions a state can take to address environmental injustice,
we construct an ordinal variable based on a Guttman scale, with scores ranging from zero to five
(Table 1). Guttman scales measure the extent to which a series of items is distributed
unidimensionally (Guest 2000). “Guttman scaling, also known as scalogram analysis and
cumulative scaling, is a procedure designed to order both items and subjects with respect to some
underlying cumulative dimension” (McIver and Carmines 1981, p. 41). A perfect Guttman scale
would consist of, in this case, each state having completed each level of action before they
complete the “next” level of action. However, because a perfect relationship between scale score
and item score is rarely achieved, this type of scale can be expected to have a certain level of
error.
Guttman (1950) designed a way to assess error, called the minimization of error.
Minimization of error is measured by counting the least number of responses that must be
changed to transform a response pattern to fit an ideal scale. As long as the coefficient of
reproducibility (CR), a measure of the unidimensionality of the items in scale, has a value of .90
or higher a Guttman scale can be used (McIver and Carmines 1981). The formula below shows
how the coefficient of reproducibility is calculated.
CR = 1.0 – (# errors)/ [(# items) x (# respondents)]
The scale score assignment is based upon the nearest ideal predicted response pattern (McIver
and Carmines 1981).
A Guttman scale is appropriate in the measurement of environmental justice policy
because it does not merely count the number of actions a state has taken. It instead assigns those
states that have completed higher levels of policy action a higher overall score. In a well-
constructed scale, these states also would have taken lower levels of action. Therefore, a score
of one is assigned to states that have completed an environmental justice study. A score of zero
is assigned to states that have taken no action towards remedying environmental injustice. A
score of two is assigned to states that have established an environmental justice commission or
created an environmental justice office within one of their existing agencies. A score of three is
assigned to states that have attempted to pass legislation aimed at addressing and alleviating
TABLE 1: State Action towards Environmental Justice
State
Study
Agency
or
Board
Legislative
Attempt
Procedural
Legislation
Substantive
Legislation
Score
8
Convention