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The large sample size fallacy

BACKGROUND Significance in the statistical sense has little to do with significance in the common practical sense. Statistical significance is a necessary but not a sufficient condition for practical significance. Hence, results that are extremely statistically significant may be highly nonsignificant in practice. The degree of practical significance is generally determined by the size of the observed effect, not the p-value. The results of studies based on large samples are often characterized by extreme statistical significance despite small or even trivial effect sizes. Interpreting such results as significant in practice without further analysis is referred to as the large sample size fallacy in this article. AIM The aim of this article is to explore the relevance of the large sample size fallacy in contemporary nursing research. RESULTS Relatively few nursing articles display explicit measures of observed effect sizes or include a qualitative discussion of observed effect sizes. Statistical significance is often treated as an end in itself. CONCLUSION Effect sizes should generally be calculated and presented along with p-values for statistically significant results, and observed effect sizes should be discussed qualitatively through direct and explicit comparisons with the effects in related literature.

Customer segmentation based on buying and returning behaviour

Purpose – The purpose of this paper is twofold: first, to empirically test whether a “one size fits all” strategy fits the fashion e-commerce business and second, to evaluate whether consumer returns are a central aspect of the creation of profitability and, if so, to discuss the role of returns management (RM) in the supply chain strategy. Design/methodology/approach – Transactional sales and return data were analysed and used to categorise customers based on their buying and returning behaviours, measuring each customers net contribution margins. Findings – The e-commerce business collects a vast quantity of data, but these data are seldom used for the development of service differentiation. This study analysed behaviour patterns and determined that the segmentation of customers on the basis of both sales and return patterns can facilitate a differentiated service delivery approach. Research limitations/implications – This research empirically supports the theory that customer buying and returning beha...

(R)e‐tail borrowing of party dresses: an experimental study

Purpose – The main purpose of this study is to increase the understanding of consumer behaviour with respect to (r)e‐tail borrowing, performed under different (more or less generous) delivery and return policies.Design/methodology/approach – The study was designed as a randomised controlled experiment with a random sample strategy. Among the 192,482 Swedish customers who had made an order at nelly.com during the previous 12 months and were to receive the quarterly nelly.com newsletter in November 2010 by e‐mail, 4,000 were randomly selected and randomised into four groups of 1,000 in each group.Findings – The experiment revealed certain purchase and return patterns that support the conclusion that (r)e‐tail borrowing behaviour exists in fashion e‐commerce. Evidence was also found that lenient delivery and returns policies seem to reinforce (r)e‐tail borrowing behaviour, albeit not always in expected ways.Practical implications – Differences in delivery and return policies seem to impact consumer purchase ...

Real e-customer behavioural responses to free delivery and free returns

This study aims to explore the influence of free delivery and free returns on the purchasing and return behaviour of real e-customers in the marketplace. To accomplish this goal, we conducted the study as a fully randomised and controlled experiment in cooperation with nelly.com, a Nordic e-commerce site that specialises in fashion and beauty. Our results suggest that a lenient delivery policy is associated with increased order frequency, decreased average value of purchased items, increased probability of return, and increased average value of returned items. In addition, a lenient return policy was found to be associated with increased order frequency, a decrease in the average value of orders, a decrease in the average value of purchased items, and increased probability of return. However, the effect sizes are generally small, and we conclude that factors such as legislation and competition often force e-tailers to offer free delivery and free returns even though such offers probably would not have been profitable otherwise.

The impact of sample non-normality on ANOVA and alternative methods

In this journal, Zimmerman (2004, 2011) has discussed preliminary tests that researchers often use to choose an appropriate method for comparing locations when the assumption of normality is doubtful. The conceptual problem with this approach is that such a two-stage process makes both the power and the significance of the entire procedure uncertain, as type I and type II errors are possible at both stages. A type I error at the first stage, for example, will obviously increase the probability of a type II error at the second stage. Based on the idea of Schmider et al. (2010), which proposes that simulated sets of sample data be ranked with respect to their degree of normality, this paper investigates the relationship between population non-normality and sample non-normality with respect to the performance of the ANOVA, Brown-Forsythe test, Welch test, and Kruskal-Wallis test when used with different distributions, sample sizes, and effect sizes. The overall conclusion is that the Kruskal-Wallis test is considerably less sensitive to the degree of sample normality when populations are distinctly non-normal and should therefore be the primary tool used to compare locations when it is known that populations are not at least approximately normal.

The double marginalization problem of transfer pricing: Theory and experiment

In this paper, we find that the idea of using optional two-part tariffs as a basis for tariff renegotiations in a bilaterally monopoly setting is a solution to the double marginalization problem that theoretically (1) creates a stable equilibrium, (2) at the overall efficient level, (3) without the presence of a central management. Through experimental testing, we find that the efficiency of this mechanism is significantly higher than the efficiency of simple direct negotiation, both under symmetrically and asymmetrically distributed information.

Seasonality of cargo theft at transport chain locations

Purpose – The purpose of this paper is to describe the seasonal patterns of reported cargo theft value and frequency in Europe, Middle East, and Africa (EMEA)countries with respect to different transport chain locations. Design/methodology/approach – This study is based on a system-theoretical approach, which emphasizes a holistic rather than an atomistic view. The research method used in this paper is deductive; the analysis is based on the data taken from Incident Information Service (IIS), a transport-related crime database of Transported Asset Protection Association (TAPA) EMEA; and the result is analyzed and discussed within a frame of reference based on supply chain risk management and criminology theories. Findings – There are seasonal variations in cargo thefts at different transport chain locations during particular months of the year as well as days of the week; however, each transport chain location has a different pattern. Indeed, hot spots, modus operandi, theft-endangered objects, and handling methods change frequently during the period under study. However, the basic theoretical frame of reference continues to be the same. Research limitations/implications – This study is based on theoretical deduction using official statistics regarding antagonistic threats. Its geographical limitation to the EMEA is owing to the limitations of the utilized database, although the frame of reference can be applied to analyze antagonistic threats against transport chains globally. Practical implications – This study is limited by the content and classification within the TAPA EMEA IIS database; nevertheless, this database is the best available one, with reports originating mainly from the industry itself, as different TAPA members anonymously report their losses. Originality/value – This paper is one of the first on supply chain risk management that uses actual crime statistics reported by the industry itself to analyze the occurrence of cargo theft by focusing on the value of the vehicle/goods stolen from transport chain locations.

Using axillary temperature to approximate rectal temperature in newborns

Various factors have been shown to potentially affect the difference between axillary and rectal temperature measurements in newborns. We aimed to explore their roles and, if possible, to construct a formula that explained the difference.

Total productive maintenance in support processes: an enabler for operation excellence

In order to stay competitive in todays marketplace, it is vital to reduce activities that do not create value. Lean production has in the last decade been seen as a philosophy to reduce non-value time. The office environment often presents a major improvement opportunity to reduce non-value time. Lean contributes positively to business performance applied in a manufacturing context and is also suggested to do the same in a service context. The purpose of the paper is to analyse and determine how total productive maintenance (TPM) can be applied within the support process and to identify effects from an employee and business perspective. A case study has been performed and a qualitative research approach was selected. Empirical data were gathered by using semi-structured interviews at one case company, but from several teams that had applied TPM. The result was then used as an inductive approach to explore how TPM can be applied in a support process. To implement and apply TPM within an office context, it should be structured in three steps (i) define, (ii) implement and (iii) sustain. TPM should be conducted as a part of the ordinary day-to-day work. The planning and discussions connected to TPM can be included in regular daily departmental ‘stand-up meetings’ involving everybody. The work with 5S and maintenance should also be a part of the TPM structure, connecting it as a system and not as an isolated activity. TPM can create value from both a business and an employee perspective. In the employee perspective, TPM reduces the risk of missing/forgetting areas of responsibility and creates more involvement. In the business perspective, objectives such as cost and quality are improved, but TPM also enables the reduction of waste.

Neonatal Intensive Care Practices: Perceptions of Parents, Professionals, and Managers

PURPOSE:This article explores the differences and similarities in opinions of neonatal intensive care issues between parents, neonatal intensive care unit (NICU) healthcare professionals (nurses and physicians), and managers (neonatal unit managers and pediatric division managers). METHOD:An exploratory survey (n = 624) was conducted in Sweden during 2012-2013 on the basis of a validated questionnaire composed of 92 neonatal care-related Likert items. A total of 141 parents, 443 professionals, and 40 managers completed the survey. The parents were recruited consecutively from 5 NICUs of the Västra Götaland region in Sweden and the professionals and managers from all 40 NICUs in Sweden. Data were analyzed with analysis of variances, and post hoc analyses were conducted through pairwise t tests with Bonferroni corrections. RESULT:Professionals and managers differed significantly on 1 item. Parents, however, found 54 items significantly less important than professionals did, but found only 4 to be significantly more important than professionals did. CONCLUSIONS:In line with previous research, we found that a gap exists between views of neonatal intensive care practices, with parents on one side and professionals and managers on the other. The nature of this gap, however, differs substantially from previous research, where parents found many items to be more important than professionals did. To develop and improve neonatal intensive care, this gap must be acknowledged and addressed, both in research and in practice. NICU managers need to develop strategies and routines that allow professionals to understand and adjust to the specific priorities of individual parents and families.