When does market success indicate superior merit? We show that when consumer choices between products with equal prices depend on quality but also past popularity, more popular are not necessarily of higher quality. Rather, a medium level popularity may be associated lower than levels popularity. Using formal model, we this kind nonmonotonic association occurs reinforcing processes strong. More...

prevalence of spinal cord injury (sci) in iran is considerable and developing a national registry is substantial. registry can be a foundation of efforts for patient care improvement, clinical research facilitation, preventative strategy formulation and policymaking for better support of patients. with respect to long-term and multiple consequents of the lesions that will have a negative impact...

In many published articles, there is still no mention of quality control processes, which might be an indication of the insufficient importance the researchers attach to undertaking or reporting such processes. However, quality control of data is one of the most important steps in research projects. Lack of sufficient attention to quality control of data might have a detrimental effect on the r...