Spatial and temporal distribution of solute leaching in heterogeneous soils: analysis and application to multisampler lysimeter data

Accurate assessment of the fate of salts, nutrients, and pollutants in natural, heterogeneous soils requires a proper quantification of both spatial and temporal solute spreading during solute movement. The number of experiments with multisampler devices that measure solute leaching as a function of space and time is increasing. The breakthrough curve (BTC) can characterize the temporal aspect of solute leaching, and recently the spatial solute distribution curve (SSDC) was introduced to describe the spatial solute distribution. We combined and extended both concepts to develop a tool for the comprehensive analysis of the full spatio-temporal behavior of solute leaching. The sampling locations are ranked in order of descending amount of total leaching (defined as the cumulative leaching from an individual compartment at the end of the experiment), thus collapsing both spatial axes of the sampling plane into one. The leaching process can then be described by a curved surface that is a function of the single spatial coordinate and time. This leaching surface is scaled to integrate to unity, and termed S can efficiently represent data from multisampler solute transport experiments or simulation results from multidimensional solute transport models. The mathematical relationships between the scaled leaching surface S, the BTC, and the SSDC are established. Any desired characteristic of the leaching process can be derived from S. The analysis was applied to a chloride leaching experiment on a lysimeter with 300 drainage compartments of 25 cm2 each. The sandy soil monolith in the lysimeter exhibited fingered flow in the water-repellent top layer. The observed S demonstrated the absence of a sharp separation between fingers and dry areas, owing to diverging flow in the wettable soil below the fingers. Times-to-peak, maximum solute fluxes, and total leaching varied more in high-leaching than in low-leaching compartments. This suggests a stochastic–convective transport process in the high-flow streamtubes, while convection–dispersion is predominant in the low-flow areas. S can be viewed as a bivariate probability density function. Its marginal distributions are the BTC of all sampling locations combined, and the SSDC of cumulative solute leaching at the end of the experiment. The observed S cannot be represented by assuming complete independence between its marginal distributions, indicating that S contains information about the leaching process that cannot be derived from the combination of the BTC and the SSDC.

The effects of clustered data on standard error estimates in covariance structure analysis : a field data application

Purpose – The purpose of this article is to present an empirical analysis of complex sample data with regard to the biasing effect of non-independence of observations on standard error parameter estimates. Using field data structured in the form of repeated measurements it is to be shown, in a two-factor confirmatory factor analysis model, how the bias in SE can be derived when the non-independence is ignored.

Design/methodology/approach – Three estimation procedures are compared: normal asymptotic theory (maximum likelihood); non-parametric standard error estimation (naïve bootstrap); and sandwich (robust covariance matrix) estimation (pseudo-maximum likelihood).

Findings – The study reveals that, when using either normal asymptotic theory or non-parametric standard error estimation, the SE bias produced by the non-independence of observations can be noteworthy.

Research limitations/implications – Considering the methodological constraints in employing field data, the three analyses examined must be interpreted independently and as a result taxonomic generalisations are limited. However, the study still provides “case study” evidence suggesting the existence of the relationship between non-independence of observations and standard error bias estimates.

Originality/value – Given the increasing popularity of structural equation models in the social sciences and in particular in the marketing discipline, the paper provides a theoretical and practical insight into how to treat repeated measures and clustered data in general, adding to previous methodological research. Some conclusions and suggestions for researchers who make use of partial least squares modelling are also drawn.

Modeling data processing activity to assess the internal control function

This thesis describes research that was conducted into the potential of modeling the activities of the Data Processing Department as an aid to the computer auditor. A methodology is composed to aid in the evaluation of the Internal Controls, particularly the General Controls relative to computer processing. Consisting of three major components, the methodology enables the auditor to model the presumed activities of the Data Processing Department against the actual activities, as recorded on the Operating System Log. The first component of the methodology is the construction and loading of a model of the presumed activities of the Data Processing Department from its verbal, scheduled, and reported activities. The second component is the generation of a description of the actual activities of the Data Processing Department from the information recorded on the Operating System Log. This is effected by reducing the Operating System Log to the format described by the Standard Audit File concept. Finally, the third component in the methodology is the modeling process itself. This is in fact a new analysis technique proposed for use by the EDP auditor. The modeling process is composed of software that compares the model developed and loaded in the first component, with the description of actual activity as collated by the second component. Results from this comparison are then reviewed by the auditor, who determines if they adequately depict the situation, or whether the models description as specified in the first component requires to be altered, and the modeling process re-initiated. In conducting the research, information and data from a production installation was used. Use of the ‘real-world’ input proved both the feasibility of developing a model of the reported activities of the Data Processing Department, and the adequacy of the operating system log as a source of information to report the departments actual activities. Additionally, it enabled the involvement and comment of practicing auditors. The research involved analysis of the effect of EDP on the audit process, structure of the EDP audit process, data reduction, data structures, model formalization, and model processing software. Additionally, the Standard Audit File concept was verified through its use by practising auditors, and expanded by the development of an indexed data structure, which enabled its analysis to be conducted interactively. Results from the trial implementation of the research software and methodology at a production installation confirmed the research hypothesis that the activities of the Data Processing Department could be modelled, and that there are substantial benefits from the EDP auditor in analysing this process. The research in fact provides a new source of information, and develops a new analysis technique for the EDP auditor. It demonstrates the utilization of computer technology to monitor itself for the audit function, and reasserts auditor independence by providing access to technical detail describing the processing activities of the computer.

Financial crisis and central bank independence and governance (CBIG)

This study examines the impact of Asian financial crisis on central bank independence and governance in the Asia Pacific. It applies a unique CBIG index-model for 36 countries for the period 1991 to 2005. This paper examines changes in the CBIG in the Asia Pacific before and after the Asian financial crisis in 1997. It applies a panel data pooled regression model and finds that the Asian financial crisis dummy is significantly different in the post-crisis period compared to the pre-crisis period. As a result the improved CBIG in the post-crisis period has contributed to lower the inflation in the entire region.

Auditor independence : shared meaning between the demand and supply sides of the audit services market?

Purpose – The purpose of the paper is to examine the extent to which there is shared meaning of the concept of auditor independence between the three major groups of parties on the demand and supply sides of the audit services market – auditors, financial report preparers and financial report users.

Design/methodology/approach – The paper utilises the measurement of meaning framework (semantic differential analysis) originally proposed by Osgood et al. in 1957. The framework is used to investigate the extent to which there is shared meaning (agreement in interpretations) of the independence concept, in response to alternative audit engagement case contexts, between key parties to the financial reporting communication process. The study's research data was collected in the period March 2004-May 2005.

Findings – Findings indicate a robust and stable single-factor cognitive structure within which the research participants interpret the connotative meaning of the auditor independence concept. An analysis of the experimental cases finds similarities in connotations (interpretations) of an audit firm's independence for the participant groups for most cases, with the exception of cases involving the joint provision of audit and non-audit (taxation) services.

Research limitations/implications – The usual external validity threat that applies to experimental research generally applies to the study. That is, the results may not be generalisable to settings beyond those examined in the study. An important implication of the study is that it emphasises the continuing problematic nature of the joint provision of audit and non-audit services, even in situations where the non-audit services comprise only traditional taxation services.

Originality/value – The study is the first to examine the concept of auditor independence by means of the Osgood et al. measurement of meaning research framework using, as research participants, the three major groups on the demand and supply sides of the audit services market.

The role of board independence in mitigating agency problem II in Australian family firms

We investigate the impact of board independence on earnings management on a sample of family controlled firms listed on the Australian Securities Exchange (ASX). Using panel data over the period 2000–2004, we find evidence of earnings management among family controlled firms in Australia, an environment of high investor protection and private benefits of control. Findings show that a higher proportion of independent directors on boards is effective in reducing earnings management, thereby mitigating agency problems associated with entrenchment and expropriation in family firms. We also find that managers of family firms are less aggressive in managing earnings via discretionary long-term accruals compared to non-family firms.

Using the functional independence measure to assess adults with cerebral palsy: an exploratory report

The Functional Independence Measure (FIM) was selected as an assessment to be conducted annually with adults attending The Spastic Centre of New South Wales (SCNSW), Australia, an organisation specifically for individuals with cerebral palsy. Service-providers were trained in the administration of the FIM and in the use of a customised data base. Initially 173 adults with cerebral palsy were assessed, this number included 135 individuals in supported and open employment. The FIM is currently being used to assess all adults attending the SCNSW as part of an annual review. The data from this ongoing assessment procedure will assist in lobbying government to ensure that individuals have access to the attendant care services that they require to function optimally in the community and will provide a longitudinal data base for study of some of the effects of the ageing process on individuals with cerebral palsy. A case study is presented which illustrates the use of the FIM with a couple who live independently in the community.

Do individual auditors affect audit quality? Evidence from archival data

We examine whether and how individual auditors affect audit outcomes using a large set of archival Chinese data. We analyze approximately 800 individual auditors and find that they exhibit significant variation in audit quality. The effects that individual auditors have on audit quality are both economically and statistically significant, and are pronounced in both large and small audit firms. We also find that the individual auditor effects on audit quality can be partially explained by auditor characteristics, such as educational background, Big N audit firm experience, rank in the audit firm, and political affiliation. Our findings highlight the importance of scrutinizing and understanding audit quality at the individual auditor level.

Additional weekend therapy may reduce length of rehabilitation stay after stroke: a meta-analysis of individual patient data

QUESTIONS: Among people receiving inpatient rehabilitation after stroke, does additional weekend physiotherapy and/or occupational therapy reduce the length of rehabilitation hospital stay compared to those who receive a weekday-only service, and does this change after controlling for individual factors? Does additional weekend therapy improve the ability to walk and perform activities of daily living, measured at discharge? Does additional weekend therapy improve health-related quality of life, measured 6 months after discharge from rehabilitation? Which individual, clinical and hospital characteristics are associated with shorter length of rehabilitation hospital stay? DESIGN: This study pooled individual data from two randomised, controlled trials (n=350) using an individual patient data meta-analysis and multivariate regression. PARTICIPANTS: People with stroke admitted to inpatient rehabilitation facilities. INTERVENTION: Additional weekend therapy (physiotherapy and/or occupational therapy) compared to usual care (5 days/week therapy). OUTCOME MEASURES: Length of rehabilitation hospital stay, independence in activities of daily living measured with the Functional Independence Measure, walking speed and health-related quality of life. RESULTS: Participants who received weekend therapy had a shorter length of rehabilitation hospital stay. In the un-adjusted analysis, this was not statistically significant (MD -5.7 days, 95% CI -13.0 to 1.5). Controlling for hospital site, age, walking speed and Functional Independence Measure score on admission, receiving weekend therapy was significantly associated with a shorter length of rehabilitation hospital stay (β=7.5, 95% CI 1.7 to 13.4, p=0.001). There were no significant between-group differences in Functional Independence Measure scores (MD 1.9 points, 95% CI -2.8 to 6.6), walking speed (MD 0.06 m/second, 95% CI -0.15 to 0.04) or health-related quality of life (SMD -0.04, 95% CI -0.26 to 0.19) at discharge. DISCUSSION: Modest evidence indicates that additional weekend therapy might reduce rehabilitation hospital length of stay.

Partner-scale economies, service bundling and auditor independence in the Australian self-managed superannuation (pension) fund industry

Using proprietary Australian Taxation Office (ATO) data, this study examines audit pricing, service bundling and independence issues in the self-managed superannuation fund (SMSF) sector, the fastest growing and largest segment of the Australian $2 trillion retirement savings industry. We consider the impact of partner-level scale effects for a large sample of SMSF audits for the three years to June 2010. After controlling for factors known to determine audit fees, we find evidence of fee discounting by partners with large client portfolios. However, when the dependent variable is redefined to the total 'bundle' of services (including audit and non-audit fees), the firms of partners with larger client portfolios are shown to earn bundling fee premiums. This finding suggests industry specialists price strategically using audits as a conduit to supply higher margin non-audit services (NAS) to clients with more resources. Last, we find no evidence the supply of NAS impairs auditor independence, alleviating joint supply concerns raised in the Cooper Review.