Holthausen and Watts (2001) classify value relevance
studies in three categories, and any individual study may
be in more than one of them: (i) “Relative association studies”,
which, like this present study, compare the association
between the market value of shares (or changes in
those values) and various forms of measurement, such as
an existing accounting standard, or one that is being proposed.
These studies normally compare the R2 of regression
models, in which an accounting standard with a higher R2
is evaluated as more relevant; (ii) “Incremental association
studies”, which investigate whether the accounting component
analyzed serves as an indicator of figures such as, for
example, profit or returns, over periods of time (it being important to include other variables). A factor is considered
to be relevant if its estimated regression coefficient is
significantly different from zero; and (iii) “Marginal information
content studies”, which investigate whether a given
factor increases investors’ power in relation to the information
available. Typically, event study methodologies are
used, in which the interest lies in assessing whether the
availability of certain information is associated with alterations
of asset value (price reactions) – in which reactions
are considered to be indications of relevance