182
the basis of the structure of the evaluation, in the case of thermometers realized by
the transduction effect of thermal expansion. And thus, for a property already known
to be comparable in terms of order, appropriate conditions on the way the property
is evaluated may help justify the hypothesis that distances/intervals, and therefore
units (though without a “natural” zero), are also meaningful. Such a general characterization is not limited to physical properties: Indeed, this can be understood as the
rationale of simultaneous conjoint measurement (Luce & Tukey, 1964) and Rasch
measurement (Rasch, 1960), as also discussed in Sect. 4.4.1:
45
the fact that the evaluation fulfills given conditions leads one to infer that the evaluated property may
have a structure richer than the observed one.
The attribution of an unobserved feature to a property is clearly an important and
consequential move. While according to condition (C1) NOIR would be considered
a feature of properties, known through their means of comparison, condition (C2)
suggests a more cautious position that NOIR is explicitly a feature of evaluations,
and only in a derived and more hypothetical way a feature of evaluated properties.
That is why we propose that NOIR are examples of Property Evaluation Types
(Giordani & Mari, 2012). This is along the same lines as Stevens’ “types of scales
of measurement”, but with the acknowledgment that such types are more generally
features of evaluations, and not only of measurements. This position allows us to
take into account the fact that the same property may be evaluated by means of
evaluations of different types,
46
so that the usual property-related terms—“nominal
1. A property is known only via a single transduction effect: for example, temperature can be
transduced to a single kind of thermometric fluid (e.g., alcohol). In this case, the hypothesis of
linearity is only grounded on the meta-hypothesis of simplicity.
2. A property is known via multiple transduction effects related to the same transduction principle: for example, temperature can be transduced to different kinds of thermometric fluid (e.g.,
alcohol and mercury). In this case, if (for example) it were discovered that the temperature that
produces the midpoint in volume between the volumes produced by two fixed points (e.g., the
freezing and boiling points of water at sea level) is the same for different fluids, the hypothesis
of linearity gains more plausibility. (As it happens, this is not exactly the case for mercury and
alcohol.)
3. A property is known via multiple transduction principles: for example, temperature can also be
transduced to electric tension, via the thermoelectric effect. In this case, if (for example) it were
discovered that the temperature that produces the midpoint in volume between the volumes
produced by the two fixed points and the temperature that produces the midpoint in tension
between the tensions produced by the same fixed points are the same for different bodies, the
hypothesis of linearity gains more plausibility.
4. A property becomes part of a nomic network (see Sect. 6.6.2); if, for example, a law is discovered that connects proportional differences of temperature of a given body to transferred heats,
the hypothesis of linearity gains even more plausibility.
45 For an extensive presentation of conjoint measurement, see Michell (1990: ch. 4), where conjoint
measurement is introduced as a “general way […] in which evidence corroborating the hypothesis
[that a property is quantitative] may be obtained” (p. 67). In the light of the discussion in Sect.
3.4.2, a method of quantification is not necessarily a method of measurement: hence a more correct
term for conjoint measurement would be “conjoint quantitative evaluation”.
46 For example, the diameter of objects, whose evaluation is usually of ratio type, may be evaluated
by means of a sequence of sieves of smaller and smaller opening, where each sieve is identified by
6 Values, scales, and the existence of properties
the basis of the structure of the evaluation, in the case of thermometers realized by
the transduction effect of thermal expansion. And thus, for a property already known
to be comparable in terms of order, appropriate conditions on the way the property
is evaluated may help justify the hypothesis that distances/intervals, and therefore
units (though without a “natural” zero), are also meaningful. Such a general characterization is not limited to physical properties: Indeed, this can be understood as the
rationale of simultaneous conjoint measurement (Luce & Tukey, 1964) and Rasch
measurement (Rasch, 1960), as also discussed in Sect. 4.4.1:
45
the fact that the evaluation fulfills given conditions leads one to infer that the evaluated property may
have a structure richer than the observed one.
The attribution of an unobserved feature to a property is clearly an important and
consequential move. While according to condition (C1) NOIR would be considered
a feature of properties, known through their means of comparison, condition (C2)
suggests a more cautious position that NOIR is explicitly a feature of evaluations,
and only in a derived and more hypothetical way a feature of evaluated properties.
That is why we propose that NOIR are examples of Property Evaluation Types
(Giordani & Mari, 2012). This is along the same lines as Stevens’ “types of scales
of measurement”, but with the acknowledgment that such types are more generally
features of evaluations, and not only of measurements. This position allows us to
take into account the fact that the same property may be evaluated by means of
evaluations of different types,
46
so that the usual property-related terms—“nominal
1. A property is known only via a single transduction effect: for example, temperature can be
transduced to a single kind of thermometric fluid (e.g., alcohol). In this case, the hypothesis of
linearity is only grounded on the meta-hypothesis of simplicity.
2. A property is known via multiple transduction effects related to the same transduction principle: for example, temperature can be transduced to different kinds of thermometric fluid (e.g.,
alcohol and mercury). In this case, if (for example) it were discovered that the temperature that
produces the midpoint in volume between the volumes produced by two fixed points (e.g., the
freezing and boiling points of water at sea level) is the same for different fluids, the hypothesis
of linearity gains more plausibility. (As it happens, this is not exactly the case for mercury and
alcohol.)
3. A property is known via multiple transduction principles: for example, temperature can also be
transduced to electric tension, via the thermoelectric effect. In this case, if (for example) it were
discovered that the temperature that produces the midpoint in volume between the volumes
produced by the two fixed points and the temperature that produces the midpoint in tension
between the tensions produced by the same fixed points are the same for different bodies, the
hypothesis of linearity gains more plausibility.
4. A property becomes part of a nomic network (see Sect. 6.6.2); if, for example, a law is discovered that connects proportional differences of temperature of a given body to transferred heats,
the hypothesis of linearity gains even more plausibility.
45 For an extensive presentation of conjoint measurement, see Michell (1990: ch. 4), where conjoint
measurement is introduced as a “general way […] in which evidence corroborating the hypothesis
[that a property is quantitative] may be obtained” (p. 67). In the light of the discussion in Sect.
3.4.2, a method of quantification is not necessarily a method of measurement: hence a more correct
term for conjoint measurement would be “conjoint quantitative evaluation”.
46 For example, the diameter of objects, whose evaluation is usually of ratio type, may be evaluated
by means of a sequence of sieves of smaller and smaller opening, where each sieve is identified by
6 Values, scales, and the existence of properties