Pedigree matrix to assess assumptions

 

The pedigree matrix for assessing the potential value-ladenness of assumptions is presented in Table 1. For a general introduction to the concept of pedigree matrix, we refer to the description of the NUSAP system in this tool catalogue. The criteria are discussed below.

 

 


Pedigree matrix for the assessment of the potential value-ladenness of assumptions 

Influence of situational limitations
The choice for an assumption can be influenced by situational limitations, such as limited availability of data, money, time, software, tools, hardware, and human resources. In absence of these restrictions, the analyst would have made a different assumption.
Although indirectly these limitations might be of a socio-political nature (e.g., the institute the analyst works for has other priorities and has a limited budget for the analyst’s work), from the analyst’s point of view these limitations are given. It can therefore be seen as primarily producing value-ladenness in a practical sense.
 
Plausibility
Although it is often not possible to assess whether the approximation created by the assumption is in accordance with reality, mostly an (intuitive) assessment can be made of the plausibility of the assumption.
If an analyst has to revert to fictive or speculative assumptions, the room for epistemic value-ladenness will often be larger. To some extent a fictive or speculative assumption also leaves room for potential disciplinary and socio-political value-ladenness. This is, however, dealt with primarily in the criteria ‘agreement among peers’ and ‘agreement among stakeholders’ respectively.
 
Choice space
The choice space indicates to which degree alternatives were available to choose from when making the assumption. In general, it can be said that a large choice space leaves more room for the epistemic preferences of the analyst. Often, the potential for value-ladenness in an epistemic sense is larger in case of a larger choice space. A large choice space will to some extent also leave more room for disciplinary and socio-political value-ladenness. These are however primarily dealt with in the criteria ‘agreement among peers’ and ‘agreement among stakeholders’ respectively.
 
Agreement among peers
An analyst makes the choice for a certain assumption based on his or her knowledge and perspectives regarding the issue. Other analysts might have made different assumptions. The degree to which the choice of peers is likely to coincide with the analyst’s choice is expressed in the criterion ‘agreement among peers’. These choices may be partly determined by the disciplinary training of the peers, and by their epistemic preferences. This criterion can thus be seen connected to value-ladenness in a disciplinary sense and in a epistemic sense.

Agreement among stakeholders
Stakeholders, though mostly not actively involved in carrying out assessments, might also choose a different assumption in case they were asked to give their view. The degree to which it is likely that stakeholders agree with the analyst’s choice is expressed in the criterion ‘intersubjectivity among stakeholders’. This will often have to do with the socio-political perspective of the stakeholders on the issue at hand and this criterion can therefore be seen as referring to value-ladenness in a socio-political sense.
 
Sensitivity to view and interests of the analyst
Some assumptions may be influenced, consciously or unconsciously, by the view and interests of the analyst making the assumption. The analyst’s epistemic preferences, and his cultural, disciplinary and personal background may influence the assumption that is eventually chosen. The influence of the analyst’s disciplinary background on the choices regarding an assumption and the influence of his epistemic preferences are taken into account in the criteria ‘agreement among peers’, ‘plausibility’ and ‘choice space’. In this criterion the focus is on the room for value-ladenness in a socio-political sense.
 
Influence on results

In order to be able to pinpoint important value-laden assumptions in the calculation chain it is not only important to analyse the potential value-ladenness of the assumptions, but also to assess the influence on the end result of the assessment. Ideally, a sensitivity analysis is carried out to assess the influence of each of the assumptions on the results. In most cases, however, this will not be attainable because itrequires the building of new models. This is why the pedigree matrix includes a column ‘influence on results’.

The modes for each criterion are arranged in such a way that the lower the score, the more value-laden the assumption potentially is.

 

See also the method for critical review of assumptions in model-based assessments

 

References
P. Kloprogge, J.P. van der Sluijs and A.C. Petersen (in press) A method for the analysis of assumptions in model-based environmental assessments, Environmental Modelling & Software.
 
Kloprogge, P., J.P. van der Sluijs, A. Petersen, 2004, A method for critical review of potentially value-laden assumptions in environmental assessments. Utrecht University, Department of Science, Technology and Society.
 
Applications:
M. Craye, E. Laes, J. van der Sluijs (2009). Re-negotiating the Role of External Cost Calculations in the Belgian Nuclear and Sustainable Energy Debate. In: A. Pereira Guimaraes and S. Funtowicz. Science for Policy, Oxford University Press, pp 272-290.
 
I. Boone, Y. Van der Stede, J. Dewulf, W. Messens, M. Aerts, G. Daube, K. Mintiens (2010) NUSAP: a method to evaluate the quality of assumptions in quantitative microbial risk assessment, Journal of Risk Research, 13: 3, 337 — 352.