xx
reading comprehension ability grew from 80.2 to 91.8 [units] in the past year”)
carries different connotations than claims made only in qualitative terms (e.g., “your
child’s reading comprehension ability grew substantially in the past year”). Invoking
the language of measurement connotes epistemic authority: measurement has historically been associated with epistemic virtues such as objectivity, precision, accuracy, and overall trustworthiness, largely as a result of the highly successful history
of measurement in the physical sciences and engineering. But, prima facie, it is not
clear whether measurement processes outside of these fields actually deserve to be
associated with such authority; a worst-case scenario would be that a given field
could be invoking the language of measurement without actually understanding
what measurement is, or how its epistemic authority is secured, which in turn could
both limit the progress of the field and undermine public trust in measurement in
general.
Given this, it would seem that reaching a common understanding of measurement should be treated as an urgent goal. However, as we will explore in this book,
measurement is not understood in the same way across different fields of application. Briefly, a weak interpretation of measurement could hold that any process that
produces information about a property of an object, according to any rule, counts as
measurement: this would have the consequence that, for example, a statement of
opinion such as “my well-being has increased during the last year” would qualify.
Stronger (i.e., more restrictive) definitions of measurement add further requirements, such as that measurement must convey relational information of one specific
kind, that is, ratios of quantities (with the corollary that a property must be a quantity in order to be measurable); from this perspective, it could be argued that most if
not all processes claimed to be measurements in the human sciences are unworthy
of the label, because it is not clear that any well-defined quantities or units exist in
these fields.
Over approximately the past decade, the three of us have explored these issues
together, each motivated by an interest in reaching a common understanding about
the nature of measurement. In the course of our conversations, we have each been
forced to scrutinize the vocabulary and foundational assumptions of our respective
fields. A starting point for our work on this book was our mutual perception that the
weak interpretation (as above) was too weak—that is, producing information
according to any rule is not sufficient for measurement—and the strong interpretation (as above) was too strong—at least because we believe that the resources of
measurement science are also useful in the evaluation of non-ratio properties.
This book presents a summary of the positions we have arrived at as a result of
our collaboration. It proposes a concept system about measurement that we believe
can be useful to anyone interested in measurement of physical or psychosocial properties. Our proposal, we hope, balances the need for specificity and generality, and
as such is indeed stronger than the weak interpretation and weaker than the strong
interpretation.
We hope that even if a reader does not agree with everything we propose here,
our work will facilitate interdisciplinary communication about measurement (and
Preface
reading comprehension ability grew from 80.2 to 91.8 [units] in the past year”)
carries different connotations than claims made only in qualitative terms (e.g., “your
child’s reading comprehension ability grew substantially in the past year”). Invoking
the language of measurement connotes epistemic authority: measurement has historically been associated with epistemic virtues such as objectivity, precision, accuracy, and overall trustworthiness, largely as a result of the highly successful history
of measurement in the physical sciences and engineering. But, prima facie, it is not
clear whether measurement processes outside of these fields actually deserve to be
associated with such authority; a worst-case scenario would be that a given field
could be invoking the language of measurement without actually understanding
what measurement is, or how its epistemic authority is secured, which in turn could
both limit the progress of the field and undermine public trust in measurement in
general.
Given this, it would seem that reaching a common understanding of measurement should be treated as an urgent goal. However, as we will explore in this book,
measurement is not understood in the same way across different fields of application. Briefly, a weak interpretation of measurement could hold that any process that
produces information about a property of an object, according to any rule, counts as
measurement: this would have the consequence that, for example, a statement of
opinion such as “my well-being has increased during the last year” would qualify.
Stronger (i.e., more restrictive) definitions of measurement add further requirements, such as that measurement must convey relational information of one specific
kind, that is, ratios of quantities (with the corollary that a property must be a quantity in order to be measurable); from this perspective, it could be argued that most if
not all processes claimed to be measurements in the human sciences are unworthy
of the label, because it is not clear that any well-defined quantities or units exist in
these fields.
Over approximately the past decade, the three of us have explored these issues
together, each motivated by an interest in reaching a common understanding about
the nature of measurement. In the course of our conversations, we have each been
forced to scrutinize the vocabulary and foundational assumptions of our respective
fields. A starting point for our work on this book was our mutual perception that the
weak interpretation (as above) was too weak—that is, producing information
according to any rule is not sufficient for measurement—and the strong interpretation (as above) was too strong—at least because we believe that the resources of
measurement science are also useful in the evaluation of non-ratio properties.
This book presents a summary of the positions we have arrived at as a result of
our collaboration. It proposes a concept system about measurement that we believe
can be useful to anyone interested in measurement of physical or psychosocial properties. Our proposal, we hope, balances the need for specificity and generality, and
as such is indeed stronger than the weak interpretation and weaker than the strong
interpretation.
We hope that even if a reader does not agree with everything we propose here,
our work will facilitate interdisciplinary communication about measurement (and
Preface