Inmaterial wear experiments, such as the Ball Mill Abrasion Test (BMAT), it iscrucial to know number of specimens be used in each experiment toproduce accurate and reliable results. In BMAT, however, a structured way ofdetermining necessary balls per type material includedin experiments has not been considered date. This article shows, usingstatistical tools adhering standards that govern these...

There are several parameters that have significant influence in metal forming process. One of the most important of them is friction coefficient. Friction can change the pattern of metal flow and the force needed for deformation. It is necessary to determine the friction coefficient to study the effect of friction on metal forming process. This study is concerned with numerical and experimental...

In this paper, we consider a nonparametric permutation test on the correlation coefficient, which is applied to a significance test on regression coefficients. Because the permutation test is very computerintensive, there are few studies on small-sample properties, although we have numerous studies on asymptotic properties with regard to various aspects. In this paper, we aim to compare the per...

The one-sample paired t-test may be used to test whether the mean difference of two populations is greater than, less than, or not equal to a specific value. Because the t distribution is used to calculate critical values for the test, this test is often called the paired t-test. If the standard deviation of the differences is known, the normal distribution is used instead of the t distribution...

The present paper aims at studying factors affecting knowledge workers’ productivity in national Iranian Oil Company, using descriptive survey method. 90 experts working at staff divisions were sampled, using census method and responded to a reliably confirmed questionnaire. One sample t test revealed at α= 0.05 that individual level factors, such as competence, job satisfaction, proficiency ha...

Personalized Transductive Learning (PTL) builds a unique local model for classification of each test sample and therefore is practically neighborhood dependant. While existing PTL methods usually define the neighborhood by a predefined (dis)similarity measure, in this paper we introduce a new concept of knowledgeable neighborhood and a transductive SVM classification tree (t-SVMT) for PTL. The ...