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The purpose of this paper is to consider the concepts of individual and complete statistical power used for multiple testing and shows their relevance for determining the number of statistical tests to perform when assessing non-response bias.

A statistical power analysis of 55 survey-based research papers published in three prestigious logistics journals (International Journal of Physical Distribution and Logistics Management, Journal of Business Logistics, Transportation Journal) over the last decade was conducted.

Results show that some of the low complete power levels encountered could have been avoided if fewer tests had been used in the assessment of non-response bias.

The research offers important recommendations to scholars engaged in survey research as they assess the effects of non-respondents on research findings. By following the recommended strategies for testing non-response bias, researchers can improve the statistical power of their findings.

Utilising Item Response Theory (IRT) methodologies, the Armed Services Vocational Aptitude Battery (ASVAB) was examined for differential item functioning (DIF) on the basis of crossed gender and ethnicity variables. Both the Mantel‐Haenszel procedure and an IRT area‐based technique were utilised to assess the degree of uniform and non‐uniform DIF in a sample of ASVAB takers. Findings were mixed. At the item level, DIF fluctuated greatly. Numerous instances of DIF favouring the reference as well as the focal group were found. At the scale level, inconsistencies existed across the forms and versions. Tests varied in their tendency to be potentially biased against the focal group of interest and at times, performed contrary to expectations. Implications for the ASVAB as well as other g‐loaded selection instruments are considered.

Studies suggest that there is a shortage of minorities entering the professions of science, technology, engineering, and mathematics (STEM). This is especially the case with African American males. Several factors that impact this phenomenon are discussed in this chapter, but chiefly the impact of test anxiety and test bias on the absence of African American men in STEM. These factors are significant because society dictates that we embrace the use of tests to determine ability. However, many individuals, including African American males, suffer from test anxiety and are victims of test bias. Science, technology, engineering, mathematics are areas that rely heavily on tests results. Therefore, the impact of test anxiety and test bias as a prohibitory method of denying access to minorities, especially African American males, is worthy of investigation and discussion. The chapter explores this relationship of test anxiety and test bias to the absence of African American males in STEM. It also looks at the importance of historically Black colleges and universities in adding African American males to STEM fields. Plausible solutions to the problem are also provided.

This study analyzed 24 IELTS Task One (data explanation) prompts for task type, diagram type, subject matter, level of critical thought, and geographical references, in order to determine whether Emirati university students’ anecdotal claims of cultural bias on the IELTS academic writing exam (as experienced by the researcher in the past decade of teaching IELTS in the United Arab Emirates) are valid. The analysis found that the majority of the task types (88%) were non-process in nature (i.e. required the description of data in the form of a chart or graph, rather than the description of a process); 40% of the non-process prompts consisted of more than one diagram. The analysis revealed that 33% of the non-process prompts included bar graphs and 29% included line graphs. Pie charts appeared in 25% of the prompts and tables in only 17%. An Emirati student English preparatory program survey indicated the pie chart as the easiest to understand – a finding that may highlight a difference between the most commonly used IELTS prompt and the students’ prompt preference. A content analysis of topics found a high percentage (58%) of subject matter related to the social sciences, with 79% of the geographical references pertaining to Western contexts. An analysis of the amount of critical thought needed for graph interpretation revealed 52% of non-process prompts required some form of critical thought. The study therefore found that the cultural bias perceived by Emirati students has some validity, given the students’ socio-cultural and educational background.

Based on the referent cognitions theory (RCT), individuals compare their outcomes to a given reference point. The purpose of this study is to investigate the effect of centrality bias in subjective performance evaluation on two employees’ work behaviors; willingness to exert work effort and retaliation intention.

A 2  ×  2 × 2 between-subject real-effort task experiment was conducted on 162 Accounting and Management students. Centrality bias and level of task difficulty were each manipulated into two groups. Meanwhile, the level of performance was divided based on the average score of the real-effort task.

The experimental data were examined using MANOVA and PROCESS macro regression. It reveals that centrality bias negatively affects willingness to exert work effort through perceived procedural fairness and positively affects retaliation intention. These findings align with the RCT in explaining the perceived procedural fairness psychological mechanism and the work behavior resulting from an unfair evaluation procedure.

This study is the first of its kind to investigate the effect of centrality bias in subjective performance evaluation on positive and negative employee behaviors concurrently, which refers to the real-effort experimental task. The study demonstrates the significant impact of centrality bias on unwillingness to exert effort and adverse behavior.

The paper tests the overconfidence bias and volatility on the Ghana Stock Exchange (GSE) during the pre-Covid-19 pandemic and Covid-19 pandemic period.

The study employs pairwise Granger causality to test the presence of overconfidence bias on the Ghana stock market as well as GARCH (1,1) and GJR-GARCH (1, 1) models to understand whether overconfidence bias contributed to volatility during pre-Covid-19 pandemic and Covid-19 pandemic period. The pre-Covid-19 pandemic period spans from January, 2019 to December, 2019, and Covid-19 pandemic period spans from January, 2020 to December, 2020.

The paper finds a unidirectional Granger causality running from weekly market returns to weekly trading volume during the Covid-19 pandemic period. These results indicate the presence of overconfidence bias on the Ghana stock market during the Covid-19 pandemic period. Finally, the conditional variance estimation results showed that excessive trading of overconfident market players significantly contributes to the weekly volatility observed during the Covid-19 pandemic period.

The empirical findings demonstrate that market participants on the GSE exhibit conditional irrationality in their investment decisions during the Covid-19 pandemic period. This implies investors overreact to private information and underreact to available public information and as a result become overconfident in their investment decisions.

Findings from this paper show that there is evidence of overconfidence bias among market players on the GSE. Therefore, investors, financial advisors and other market players should be educated on overconfidence bias and its negative effect on their investment decisions so as to minimize it, especially during the pandemic period.

This study is a maiden one that underscores investors’ overconfidence bias in the wake of a pandemic in the Ghanaian stock market. It is a precursor to the overconfidence bias discourse and encourages the testing of other behavioral biases aside what is understudied during the Covid-19 pandemic period in Ghana.

Accelerated life tests on avionic PWAs (printed wiring assemblies) showed no relationship between measles and premature electrical failures. For the study, test samples with measles and crazes bridging up to 100% of the distance between adjacent conductors were exposed to different combinations of thermal cycling, humidity and DC voltage bias. The exposures were designed to accelerate electrochemical failure processes such as CAF (conductive anodicfilament) growth between conductors. The study was conducted in two phases. In Phase I, measled and non‐measled sites on six modules (including both epoxy/fibreglass and polyimide/fibreglass PWBs were tested. Bias voltages of 10,100 and 200 volts DC were applied during 10‐day tests and currents were monitored to detect the appearance of electrical shorts between individual conductor pads. Microscopic examination revealed no detectable change in the size or appearance of the measles during the exposure. Currents measured during the exposure were generally in the nanoamp range. They were similar for both measled and control sites and all sites passed the minimum criterion for insulation resistance of 500 megohms. Two of the modules were then tested at 320 and 500 volts. Short circuit failures were produced, but metallographic examination revealed them to be artifacts associated with reworked solder pads. There was no correlation between the incidence of failure and the presence of measles. In Phase II, test sites on two new polyimide/glass modules were exposed at voltages up to 500 V for a series of 5‐ or 10‐day periods, interspersed with precise measurements of insulation resistance under ambient conditions. Although no failures were produced in these tests, the ambient measurements showed some loss in insulation resistance with exposure time. Further testing revealed that the loss of insulation resistance was reversible and was unrelated to the presence or absence of measles.

This study aims to answer the question whether investment funds managers exhibit behavioural biases in their investment decisions. Furthermore, it investigates if fund managers, as a group of institutional investors, make decisions in response to central bank’s communication as well as other information in relation to various behavioural inclinations.

A comprehensive study was conducted based on a questionnaire, which is composed of three main parts exploring: (1) general information about the funds under the management of the surveyed group of fund managers, (2) factors that influence the investment process with an emphasis on the National Bank of Poland communication and (3) behavioural inclinations of the surveyed group. Cronbach’s alpha statistic was applied for measuring the reliability of the survey questionnaire and then chi-squared test was used to investigate the relationships between the answers provided in the survey.

The central bank’s communication matters for investors, but its impact on their decisions appears to be only moderate. Interest rates were found to be the most important announcements for investment fund managers. The stock market was the most popular market segment where the investments were made. The ultra-short time horizon played no, or only small, role in the surveyed fund managers’ decisions as most of them invested in a longer horizon covering 1 to 5 years. Moreover, most respondents declared that they considered in their decisions the information about market expectations published in the media. Finally, majority of the fund managers manifested limited rationality and were subject to behavioural biases, but the decisions and behavioural inclinations were independent and, in most cases, they did not influence each other.

The results reported in this study can be used in practice to better understand and to improve the fund managers’ decision-making processes.

Apart from the commonly tested behavioural biases in the group of institutional investors in the existing literature, such as loss aversion, disposition effect or overconfidence, this paper also focuses on the less intensively analysed behavioural inclinations, i.e. framing, illusion of the control, representativeness, sunk cost effect and fast thinking. The originality of this study further lies in the way the research was conducted through interviews with fund managers, who were found to be subject to behavioural biases, although those behavioural inclinations did not influence their investment decisions. This finding indicates that professionalism and collectivism in the group of institutional investors protect them from irrationality.