Examining Multiple Comparison Procedures According to Error Rate, Power Type and False Discovery Rate

Examining pairwise differences between means is a common practice of applied researchers, and the selection of an appropriate multiple comparison procedure (MCP) is important for analyzing pairwise comparisons. This study examines the performance of MCPs under the assumption of homogeneity of variances for various numbers of groups with equal and unequal sample sizes via a simulation study. MCPs are compared according to type I error rate, power type and false discovery rate (FDR). Results show that the LSD and Duncan procedures have high error rates and Scheffe’s procedure has low power; no remarkable differences between the other procedures considered were identified

Examining Growth with Statistical Shape Analysis and Comparison of Growth Models

Growth curves have been widely used in the fields of biology, zoology and medicine for assessing some measurable trait of an organism, such as height, weight, area or volume. In statistical shape analysis, a size measure is obtained using the geometrical information of an object as opposed to linear measurements. The performances of commonly used non-linear growth curves are compared by using centroid size as a size measure in a simulation study. An example is provided on the relationship between centroid size of the cerebellum and disease duration in multiple sclerosis patients

Comparison of Model Fit Indices Used in Structural Equation Modeling Under Multivariate Normality

The purpose of this study is to investigate the impact of estimation techniques and sample sizes on model fit indices in structural equation models constructed according to the number of exogenous latent variables under multivariate normality. The performances of fit indices are compared by considering effects of related factors. The Ratio Chi-square Test Statistic to Degree of Freedom, Root Mean Square Error of Approximation, and Comparative Fit Index are the least affected indices by estimation technique and sample size under multivariate normality, especially with large sample size

Acute Physiological Effects of Small-Sided Games Applied on the Hearing-Impaired National Team Soccer

The purpose of this study is to determine whether there is a difference between physiological responses to the small-sided games often applied during soccer trainings by changing the dimensions of the fields, the number of players, duration and the rules of the games. 16 sports people, who play soccer in Turkey Hearing- Impaired National soccer Team, having 31, 38±6,02 of age, 177,13±4,38 cms of height, 74,22±4,44 kgs of bodily weight, volunteered for this research.  The subjects were made to play free games with the intervals of 2 days, in different periods of 4x4, in the fields of 36mx24m, in 24 minutes in total in the forms of 1x24, 2x12, 4x6 and 6x4. After each game, a rest period of two days, and between the sets, a rest period of 4 minutes was given. Through anthropometric measurements of the subjects, their lactic acid levels in blood and the number of heart beats after small-sided games were determined. Also the difficulty levels perceived were determined with BORG scale. The data were transferred to IBM SPSS statistics 22 program and the analyses were completed. Friedman test was used to have a look whether there was a difference between descriptive statistics and dependent groups for continuous variables.At the end of the small-sided games applied in different periods and repetitions, a statistical meaningfulness was determined in the comparison of the speed of the heartbeat of the subjects that participated in the study(P<0.001). While a meaningfulness was determined in the comparison of the lactic acid amounts that appeared in the subjects (P<0.01); there was no statistical meaningfulness in the comparison of the perceived difficulty level of the small-sided games played

Comprehensive Evaluation of Reference Values of Parametric and Non-Parametric Effect Size Methods for Two Independent Groups

In the field of health and other sciences, effect size (ES) provides a scientific approach to the effectiveness of treatment or intervention. The p-value indicates whether the statistical difference depends on chance, while ES gives information about the effectiveness of the treatment or intervention, even if the difference is not significant. For this reason, ES has become a very popular measure in recent years. It depends on which ES will be used based on the distribution of data and the number of groups. In this study, parametric and non-parametric ES were evaluated for two independent groups. When the literature was examined, there were no studies aimed at evaluating the reference values of the parametric and non-parametric ES methods used for two independent groups. In this study, the reference values of parametric and non-parametric ES methods for two independent groups were re-evaluated by a simulation study. As a result, the very small reference value of parametric ES methods was determined differently from the literature. It has been seen that the reference values of non-parametric ES methods are valid in cases where the skewness is low, and new reference values have been proposed at the varying skewness level

On Comparing Survival Curves with Right-Censored Data According to the Events Occur at the Beginning, in the Middle and at the End of Study Period

In clinical practice the event of interest does not always occur equally across the study time period. Depending on the disease being investigated, the event that is of interest can occur intensively in different periods of the follow-up time. In such cases, choosing the correct survival comparison test has importance. This study aims to examine and discuss the results of survival comparison tests under some certain circumstances. A simulation study was conducted. We discussed the result of different tests such as Logrank, Gehan-Wilcoxon, Tarone-Ware, Peto-Peto, Modified Peto-Peto tests and tests belonging to Fleming-Harrington test family with (p, q) values; (1, 0), (0.5, 0.5), (1, 1), (0, 1) ve (0.5, 2) by means of Type I error rate that obtained from simulation study, when the event of interest occurred intensively at the beginning of the study, in the middle of the study and at the end of the study time period. As a result of simulation study, Type I error rate of tests is generally lower or higher than the nominal value. In the light of the results, it is proposed to re-examine the tests for cases where events are observed intensively at the beginning, middle and late periods, to carry out new simulation studies and to develop new tests if necessary

FPGA implementation of HEVC intra prediction using high-level synthesis

Intra prediction algorithm in the recently developed High Efficiency Video Coding (HEVC) standard has very high computational complexity. High-level synthesis (HLS) tools are started to be successfully used for FPGA implementations of digital signal processing algorithms. Therefore, in this paper, the first FPGA implementation of HEVC intra prediction algorithm using a HLS tool in the literature is proposed. The proposed HEVC intra prediction hardware, in the worst case, can process 35 full HD (1920×1080) video frames per second. Using HLS tool significantly reduced the FPGA development time. Therefore, HLS tools can be used for FPGA implementation of HEVC video encoder

Novel approximate absolute difference hardware

Approximate hardware designs have higher performance, smaller area or lower power consumption than exact hardware designs at the expense of lower accuracy. Absolute difference (AD) operation is heavily used in many applications such as motion estimation (ME) for video compression, ME for frame rate conversion, stereo matching for depth estimation. Since most of the applications using AD operation are error tolerant by their nature, approximate hardware designs can be used in these applications. In this paper, novel approximate AD hardware designs are proposed. The proposed approximate AD hardware implementations have higher performance, smaller area and lower power consumption than exact AD hardware implementations at the expense of lower accuracy. They also have less error, smaller area and lower power consumption than the approximate AD hardware implementations which use approximate adders proposed in the literature

An efficient FPGA implementation of versatile video coding intra prediction

Versatile Video Coding (VVC) is a new international video compression standard offering much better compression efficiency than previous video compression standards at the expense of much higher computational complexity. In this paper, an efficient FPGA implementation of VVC intra prediction for angular prediction modes of 4x4, 8x8, 16x16 and 32x32 prediction unit sizes is proposed. In the proposed FPGA implementation, four constant multiplications used in one intra angular prediction equation are implemented using two DSP blocks and two adders in FPGA. The proposed FPGA implementation of VVC intra prediction, in the worst case, can process 34 full HD (1920x1080) frames per second