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The purpose of this paper is to propose a new computational approach for parameter estimation in the Bayesian framework. A posteriori probability density functions are obtained using the polynomial chaos theory for propagating uncertainties through system dynamics. The new method has the advantage of being able to deal with large parametric uncertainties, non‐Gaussian probability densities and nonlinear dynamics.

The maximum likelihood estimates are obtained by minimizing a cost function derived from the Bayesian theorem. Direct stochastic collocation is used as a less computationally expensive alternative to the traditional Galerkin approach to propagate the uncertainties through the system in the polynomial chaos framework.

The new approach is explained and is applied to very simple mechanical systems in order to illustrate how the Bayesian cost function can be affected by the noise level in the measurements, by undersampling, non‐identifiablily of the system, non‐observability and by excitation signals that are not rich enough. When the system is non‐identifiable and an a priori knowledge of the parameter uncertainties is available, regularization techniques can still yield most likely values among the possible combinations of uncertain parameters resulting in the same time responses than the ones observed.

The polynomial chaos method has been shown to be considerably more efficient than Monte Carlo in the simulation of systems with a small number of uncertain parameters. This is believed to be the first time the polynomial chaos theory has been applied to Bayesian estimation.

Discusses computational challenges in air quality modelling (as viewed by the authors). The focus of the paper will be on Di, the “current” state‐of‐affairs. Owing to limitation of space the discussion will focus on only a few aspects of air quality modelling: i.e. chemical integration, sensitivity analysis and computational framework, with particular emphasis on aerosol issues.

Despite the growing amount of research on the social and organizational role of legitimacy, very little is known about the subtle discursive processes through which organizational changes are legitimated in contemporary society. The purpose of this paper is to explore the subtle processes of interdiscursivity and intertextuality through which an organization constructs a sense of legitimacy.

Drawing on the case of a newly privatized oil company in a transitional, post-communist economy, the authors’ research uses critical discourse analysis to analyze the annual reports, corporate press releases, and relevant media from the four years following privatization.

The authors argue for a relational understanding of legitimacy construction that emphasizes how legitimacy relies on the multiple processes of intertextuality linking corporate narratives and media texts. Corporate narratives are not produced solely by the discourses that occur at the individual and organizational levels; they are also produced by the much broader discourses that occur at the societal level.

This study’s main contribution is that it reveals the intertextual and interdiscursive construction of corporate narratives, which is a key element in understanding how discourses around privatization are interlinked and draw upon other macro-level discourses to construct legitimacy.

The purpose of this study is to explore the potential for technical accounting resources to help professional accountants exercise their performative agency.

The authors combine the integrative learning theory of truth and the concept of performativity, including two approaches to sustainability education and interventions, to construct a grid for coding the technical resources provided by the UK's Institute of Chartered Accountants in England and Wales, a pioneer in sustainability advocacy.

The findings suggest the dominance of the “predetermined and expert-determined” approach. They also reveal the emergence of three levels of performative topoi based on the relative presence of the “predetermined and expert-determined” and “process-of-seeking” approaches to professional interventions toward sustainability. The results show the profession's evolving contribution to the construction of actionable knowledge.

The main limitation of this research is that it draws on a limited corpus. In addition, the use of a binary code to represent the presence/absence of a code does not convey the code's quantitative importance.

The results are useful for those wanting to produce technical accounting resources that are more likely to help professionals build actionable knowledge and contribute to accountants' interventions toward sustainability.

Findings suggest the need for reflection on how the accounting profession can best contribute to implementing sustainability in organizations.

Few studies deconstruct professional technical resources to see how a profession can contribute to a process of societal change.