Forecasting and Management of Technology, Second Edition

5.4 Preparing Search Results

Many of the applications of search results use quantitative measures. Indeed, even when the information is qualitative, some scale or rating scheme often needs to be applied. For instance, names or a nominal scale might be attached to expert data. Or decision makers might be asked to represent their preferences from most to least preferred—this is an ordinal scale. If there are established units of measurement (e.g., numbers of publications or patents), an interval scale that measures technological development might be constructed. Finally, you might be able to assign a ratio scale to the measurement—for instance, by asking how profitable a new technology will be.

In what would become one of the most famous papers in the annals of social science, Stevens (1946) reported the conclusions of a committee tasked to provide “quantitative estimates of sensory events.” He concluded that the problem of measurement involves finding rules for assigning quantitative indicators and considering their mathematical properties. The classic alternatives for measurement scales, as developed by the committee, are shown in Table 5.11.

Table 5.11 Units of Measurement

Scale	Nature of Operations	Statistical Equivalent
Nominal	Determination of equality	Number of cases
Ordinal	Determination of greater than or less than	Percentiles
Interval	Determination of equality of intervals	Means Standard deviations
Ratio	Determination of equality of ratios	Correlations

Stevens ...