In clinical research, parameters required for sample size calculation are usually unknown. A typical approach is to use estimates from some pilot studies as the true parameters in the calculation. This approach, however, does not take into consideration sampling error. Thus, the resulting sample size could be misleading if the sampling error is substantial. As an alternative, we suggest a Bayes...

Although the commonly used Internet Service Provider’s business models based on price comparison may prove to be a successful strategy for organisations in the short term, it may be argued that a sustainable business model for the long term requires a detailed understanding of the various factors that may help ISPs in attracting future customers. This paper therefore examines the influence of a...

The individual preference effect supplements the predominant group-level explanations for the failure of groups to solve hidden profiles. Even in the absence of dysfunctional group-level processes, group members tend to stick to their suboptimal initial decision preferences due to preference-consistent evaluation of information. However, previous experiments demonstrating this effect retained t...

PURPOSE. Retinal nerve fiber layer (RNFL) thickness measured by optical coherence tomography (OCT) can be unreliable in the presence of a myopic tilted disc. The purpose of this study was to investigate the influence of the calculation circle location of spectral domain (SD)-OCT when measuring RNFL thickness in healthy subjects with myopic tilted disc. METHODS. Sixty-nine eyes with myopic tilte...

objectives: deterioration in postural control mechanisms is termed postural instability and results increased postural sway and many laboratory techniques and instruments are characterized by a wide range of neurological signs and symptoms to the medical management. thus the current study designed to assess the reliability of commonly used clinical measures of balance and determined normal valu...

background and purpose: sample size and its determination is one of the most important problems in health researches. calculating sample size for prevalence studies is one of the common questions of sample size topics. minimum sample size with least complexity is desirable in order to achieve the basic goal of these studies. this study aims to compare two formulas of sample size calculation for...

On online social networks (OSNs) such as Facebook and Twitter, the massive selfdisclosure has attracted the attention of both academic researchers and marketers. Despite of the impressive scope of this phenomenon, few studies have systematically studies why people self disclose so much on OSNs; let alone what context feature or media capabilities within OSNs will influence people’s voluntary se...

In the past, gift-giving has interested mainly anthropologists because it was taken to be a primitive mode of exchange. Recent contributions of economists acknowledge however that gift-giving is still present in modern exchange economies. In this paper gifts are characterized by motivations. Two main features of gift giving are to be explained: (in-)adequacy and (non-)reciprocity. It is argued ...

The aim of this paper to explain gift-giving by means of social approval. In a simple framework we are able to account for a number of stylized facts. These are that gift-giving is often reciprocal, that gifts tend to be inadequate, and that gift-giving is sometimes reduced after a monetary compensation is o¤ered. The implication for the interaction between gift-giving and the market institutio...

We present a theoretical model of a linear public good game in which heterogeneous players express social approval after observing contributions. The model explains how social approval is expressed and predicts positive contributions if subjects have a preference for social approval. Using a controlled laboratory experiment we test our model. In the experiment, subjects conduct computerized tas...