scholarly journals NONCORRALATED DATA ORDERED SAMPLES AS A SINGLE-ELEMENT MULTICHANNEL CONVERTER

2021 ◽  
Vol 2021 (3) ◽  
pp. 74-82
Author(s):  
R.O. Mazmanian ◽  
Keyword(s):  
Normal Distribution ◽  
Statistical Testing ◽  
Random Numbers ◽  
Single Element ◽  
Data Converter ◽  
Random Data ◽  
Chi Square ◽  
Chi Square Test ◽  
Probability Density Function Pdf ◽  
Statistical Criteria

The sufficient closeness of the medians of the ordered samples of random data to the normal distribution is used in computer systems for control, monitoring and diagnosing electric power equipment. However, it remains what other probability density function (pdf) of elements (sample statistics) have such similarities. This paper presents various methods for statistical testing hypotheses for pdf-converter channels as statistics of given sizes odd numbered and ordered samples of bounded and uniformly distributed random numbers. The use of various different criteria and the results of estimates studied under the same conditions showed a sufficient conformity of the results of tests for three statistical criteria. It made possible to draw a reasonable conclusion about the preferable use of the adapted chi-square test for assessing the congruence of analytical pdf channels of the converter with normal distribution. We also suggested using the "statistical closeness window" to define those channels of the converter that do not significantly differ from the normal distribution. In addition, we presented an empirical formula determining the dependence of the size of the window of the statistical closeness window on the sample size. The results of the research are summarized in a statistical model of a multichannel uncorrelated data converter. References 27, figures 7.

scholarly journals MULTICHANNEL CONVERTION OF RANDOM DATA WITH THE PAIR-ELEMENTS OF ORDERED SAMPLES

2021 ◽  
Vol 2021 (5) ◽  
pp. 63-75
Author(s):  
R.O. Mazmanian ◽  
Keyword(s):  
Distribution Density ◽  
Single Element ◽  
Density Functions ◽  
Probability Distribution Density ◽  
Distribution Law ◽  
Random Data ◽  
Chi Square ◽  
Mutual Dependence ◽  
Structural Differences ◽  
Probability Density Function Pdf

The concept of multichannel parallel converting of probability density function (pdf) of random data was previously used for single-element pdf-converters. In development of this concept, here we investigate converting properties of spdf-converters channels formed by the sum of the ​​pairs of ordered sample elements (order statistics). The characteristics of the conversion results as dependencies on the size of the samples and the displacement of the channels relative to the median of the samples were obtained for data with a uniform distribution density. Also where excluded the areas of mutual dependence of the density functions of the summed elements, which further where normalized together with approximating them functions. Despite the apparent structural differences, the goal of this study still was to determine the closeness of the converted data with some standard functions of the probability distribution density, in particular, with the normal distribution law. As before, the estimates of the closeness of the spdf-converter channels were obtained using the chi-square criteria. The results of the research were used to determine the size and location of the statistical closeness windows, and to construct spdf-converters statistical model. References 20, figures 14.

Prediction of Haemoglobin Level by Some Probability Distribution

2020 ◽  
Vol 9 (1) ◽  
pp. 84-88
Author(s):  
Govinda Prasad Dhungana ◽  
Laxmi Prasad Sapkota
Keyword(s):  
Probability Distribution ◽  
Normal Distribution ◽  
Goodness Of Fit ◽  
Continuous Variable ◽  
Hemoglobin Level ◽  
Chi Square ◽  
Chi Square Test ◽  
Log Normal ◽  
Two Parameters ◽  
Best Fit

 Hemoglobin level is a continuous variable. So, it follows some theoretical probability distribution Normal, Log-normal, Gamma and Weibull distribution having two parameters. There is low variation in observed and expected frequency of Normal distribution in bar diagram. Similarly, calculated value of chi-square test (goodness of fit) is observed which is lower in Normal distribution. Furthermore, plot of PDFof Normal distribution covers larger area of histogram than all of other distribution. Hence Normal distribution is the best fit to predict the hemoglobin level in future.

scholarly journals PEMILIHAN DISTRIBUSI PROBABILITAS PADA ANALISA HUJAN DENGAN METODE GOODNESS OF FIT TEST

2016 ◽  
Vol 18 (2) ◽  
pp. 139-148
Author(s):  
Togani Cahyadi Upomo ◽  
Rini Kusumawardani
Keyword(s):  
Normal Distribution ◽  
Goodness Of Fit ◽  
Gumbel Distribution ◽  
Rainfall Event ◽  
Goodness Of Fit Test ◽  
Chi Square ◽  
Chi Square Test ◽  
Log Normal ◽  
Log Normal Distribution ◽  
Pearson Iii Distribution

Rainfall event is a stochastic process, so to explain and analyze this processes the probability theory and frequency analysisare used. There are four types of probability distributions.They are normal, log normal, log Pearson III and Gumbel. To find the best probabilities distribution, it will used goodness of fit test. The tests consist of chi-square and smirnov-kolmogorov. Results of the chi-square test for normal distribution, log normal and log Pearson III was 0.200, while for the Gumbel distribution was 2.333. Results of Smirnov Kolmogorov test for normal distribution D = 0.1554, log-normal distribution D = 0.1103, log Pearson III distribution D = 0.1177 and Gumbel distribution D = 0.095. All of the distribution can be accepted with a confidence level of 95%, but the best distribution is log normal distribution.Kejadian hujan merupakan proses stokastik, sehingga untuk keperluan analisa dan menjelaskan proses stokastik tersebut digunakan teori probabilitas dan analisa frekuensi. Terdapat empat jenis distribusi probabilitas yaitu distribusi normal, log normal, log pearson III dan gumbel. Untuk mencari distribusi probabilitas terbaik maka akan digunakan pengujian metode goodness of fit test. Pengujian tersebut meliputi uji chi-kuadrat dan uji smirnov kolmogorov. Hasil pengujian chi kuadrat untuk distribusi normal, log normal dan log pearson III adalah 0.200, sedangkan untuk distribusi gumbel 2.333. Hasil pengujian smirnov kolmogorov untuk distribusi normal dengan nilai D = 0.1554, distribusi log normal dengan nilai D = 0.1103, distribusi log pearson III dengan nilai D = 0.1177 dan distribusi gumbel dengan nilai D = 0.095. Seluruh distribusi dapat diterima dengan tingkat kepercayaan 95%, tetapi distribusi terbaik adalah distribusi log normal.

scholarly journals A Clinical Study Investigating Whether the Tongue-Out Position Improves the Quality of the Anatomical Appearance of the Pharynx on CT Imaging

2021 ◽  
Vol 8 ◽  
Author(s):  
Jin-Long Wu ◽  
Rui-Gang Ge ◽  
Guang-Jian Tang
Keyword(s):  
Normal Distribution ◽  
Soft Palate ◽  
Ct Images ◽  
Chi Square ◽  
Pyriform Fossa ◽  
Kappa Test ◽  
A Value ◽  
Chi Square Test ◽  
The Difference

Objective: To evaluate the effect of using the tongue-out position on the quality of the anatomical appearance of the pharynx on computed tomography (CT) images.Methods: The data from enhanced CT thin-section images of the head and neck in 119 cases scanned were retrospectively analyzed. The cases were divided into two groups based on the position of the tip of the tongue on the images: the tongue-out group (63 cases) and non-tongue-out group (56 cases). Two observers separately evaluated the anatomy of the soft palate, uvula, palatine tonsils, epiglottis, epiglottic fossa, pyriform fossa, arytenoid folds, and tongue on all images. The Kappa test was applied to assess the consistency of scores between the two observers. In the case of data that satisfied the normal distribution, the significance of the difference in the average scores between the two groups was tested using an independent samples t-test with a value of p > 0.05. In the case of data that did not satisfy the normal distribution, the Mann–Whitney U test was adopted to test the significance of the difference in the average scores between the two groups using a value of p < 0.05. The number of cases with swallowing artifacts on the CT images in both groups was statistically analyzed and the chi-square test was used to determine whether the difference in the incidence of artifacts between the two groups was significant.Results: The Kappa test showed good consistency between the two observers scoring of the soft palate, uvula, epiglottis, epiglottic fossa, pyriform fossa, aryepiglottic folds, and tongue. The image scores of the soft palate, uvula, epiglottis, epiglottic fossa, and tongue in the tongue-out group vs. the non-tongue-out group did not satisfy the normal distribution. The Mann–Whitney U test showed that the differences in the image scores between the two groups were statistically significant in all cases (p < 0.05). The incidence of swallowing artifacts in the tongue-out group and the non-tongue-out group was 15 and 32%, respectively. The result of the chi-square test showed that the difference in the incidence of swallowing artifacts between the two groups was statistically significant (p = 0.037).Conclusion: The tongue-out position facilitated an improvement in the CT appearance of pharyngeal anatomy and was associated with a reduction in the incidence of swallowing artifacts.

Personality and Motivational Factors of U. S. Naval Academy Graduates as Indicators of Aviation Mishap Potential

1983 ◽  
Vol 27 (10) ◽  
pp. 838-842
Author(s):  
Robert A. Alkov ◽  
Michael S. Borowsky ◽  
John A. Gaynor ◽  
Karel Montor
Keyword(s):  
Normal Distribution ◽  
Motivational Factors ◽  
Personality Characteristics ◽  
Naval Academy ◽  
Chi Square ◽  
Accident Proneness ◽  
Chi Square Test ◽  
Naval Aviators

Although the concept of accident-proneness has fallen into disfavor because of the failure to statistically identify accident repeaters from their personality characteristics, it may be possible to predict mishap liability for those who enter a military flying career. The 16PF, Motivational Analysis Test and the Athletic Motivation Inventory administered to U. S. Naval Academy freshman classes were examined. Scores of over 1700 graduates from the classes of 1975-1981, who were subsequently designated as naval aviators, were studied. Using their flight hours and mishaps accumulated during the first two to five years of their flying careers, a mishap rate was calculated for low and high groups on each personal dimension. Scores were placed into ten stens within each dimension (e.g., reserved-outgoing) based on the standardization sampling of all U. S. college undergraduates. Due to the normal distribution of scores, stens 1 and 10 had very low numbers. Any rate based on so few cases was very unstable. One or two mishaps could change the rate dramatically. Therefore, the mishap rates were examined by grouping stens. A chi square test was used to determine if sten ranges differed significantly in their aircraft mishap rates. There were 9 of 67 dimensions in which the sten ranges differed significantly. These are discussed.

scholarly journals Evaluation the Best Random Component in Modified Thomas-Fiering Model in Generating Rainfall Data for Akre station

2019 ◽  
Vol 9 (2) ◽  
pp. 186-192
Author(s):  
Fawaz Kh. Aswad ◽  
Ali A. Yousif ◽  
Sayran A. Ibrahim
Keyword(s):  
Mean Squared Error ◽  
Daily Rainfall ◽  
Absolute Error ◽  
Rainfall Data ◽  
Random Numbers ◽  
Random Component ◽  
Chi Square ◽  
Daily Rainfall Data ◽  
Chi Square Test ◽  
Kolmogorov Smirnov

In this research, the effect of random component in the modified Thomas-Fiering model to generate daily rainfall data was studied, and Akre station considered a case study. A random component with special distributions: Normal random numbers, Wilson-Hilferty (W-H) transformation, truncated W-H, and Kirby modification to W-H transformation were used. The model applied to the daily rainfall data for Akre station for available years 2000–2006 and the model used to generate the rainfall data for the years 2006 and 2007. The results showed that the correlation coefficients between the observed and generated data were 0.82 for normal random numbers, 0.77 for W-H transformation, 0.89 for truncated –W –H, and 0.87 for KM to W-H transformation. The tests of Chi-square test, Kolmogorov–Smirnov test, root mean squared error (RMSE) test, and mean absolute error (MAE) test were used to compare between observed and generated data. All the results have passed the Chi-square test and Kolmogorov–Smirnov, where the calculated values were less than the tabulated value at 5% significance. For the test RMSE and MAE, the truncated W-H transform was the values of at least two. Therefore, W-H transform is the best for generating the rainfall data at Akre station

DETECTING THE AUTO-CORRELATION BETWEEN DAILY TEMPERATURE AND RELATIVE HUMIDITY TIME SERIES

Fractals ◽  
2019 ◽  
Vol 27 (02) ◽  
pp. 1950003
Author(s):  
QINGJU FAN ◽  
SHUANGGUI LIU ◽  
KEHAO WANG
Keyword(s):  
Relative Humidity ◽  
Long Range ◽  
Fluctuation Analysis ◽  
Test Statistics ◽  
Chi Square ◽  
Multifractal Detrended Fluctuation Analysis ◽  
Auto Correlation ◽  
Chi Square Test ◽  
Detrended Fluctuation ◽  
Probability Density Function Pdf

Multifractal detrended fluctuation analysis (MF-DFA) for bivariate series has been used to study the auto-correlation between temperature and relative humidity series in Wuhan city, China. The results show that long-range persistence auto-correlation exists between the temperature and relative humidity series and the auto-correlation has multifractal characteristics. For the two climate records, the contribution of single series to multifractality is analyzed by utilizing chi square ([Formula: see text]) test. By comparing the chi square test statistics of original series with those of shuffled and surrogate series, we conclude that the relative humidity is more responsible for the multifractality due to its long-range correlation, and the temperature and relative humidity series almost have the same degree of contributions to the multifractality due to a fatness of probability density function (PDF) correlation. On the whole, the relative humidity series has dominant effect in the auto-correlation.

scholarly journals Effects of Systematic Changes in Commodity Arrangement on the Satisfaction of Supermarket Customers

2021 ◽  
Vol 25 (1) ◽  
pp. 16-32
Author(s):  
Josef Tošenovský ◽  
Filip Tošenovský ◽  
Ivana Dočkalová
Keyword(s):  
Relative Frequency ◽  
Scientific Literature ◽  
Scientific Field ◽  
Statistical Testing ◽  
Chi Square ◽  
The Czech Republic ◽  
Behavioural Patterns ◽  
Chi Square Test ◽  
Product Location ◽  
Positive Effect

Purpose: The paper investigates if relocation of goods at supermarkets, practised to boost sales, bothers customers and improves financial results of the stores. To explore this, a questionnaire-based poll was run, using questions, such as “Do you mind if commodity is not permanently in the same place?”, or “While searching, do you buy anything you did not indend to buy?”. Various relations are also observed. For instance, are opinions on product relocation related in any way to age of customers? The study suggests most customers are not satisfied with changes in product location, yet the practices lead to higher sales. It turns out the business principle – only satisfied customers spend more – may not be so true. In the study, some new questions also arose and were evaluated, such as the question “Which management activities have a positive effect on customers?”.        Methodology/Approach: The paper relies on statistical testing, specifically on the chi-square test of independence and a test of differences in the relative frequency of occurrence of diverse phenomena. Real, empirical data are utilized. Findings: The analysis showed that most customers dislike looking for goods, and many of them buy items that they did not intend to purchase. Thus, a paradox occurs when entrepreneurs dissatisfy customers, yet they register higher profits. Research Limitation/Implication: The results concern a specific scientific field – microeconomic behavioural patterns at supermarkets. Originality/Value of paper: The research presented in this paper is focused on the Czech Republic where it has not been undertaken to date. Work of this kind is not cited in the scientific literature, however.

scholarly journals Biotherapic of Trypanosoma cruzi 17x controlled histopathological alterations in mice infected by this protozoon

2021 ◽  
Vol 10 (36) ◽  
pp. 110-114
Author(s):  
Patrícia Flora Sandri ◽  
Gislaine Janaina Sanchez Falkowski ◽  
Anélio Dias Nascimento Júnior ◽  
Miguel Spack ◽  
Neide Martins Moreira ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Normal Distribution ◽  
Controlled Trial ◽  
Giant Cells ◽  
World Health ◽  
Chi Square ◽  
Global Challenge ◽  
Chi Square Test ◽  
Health Organization

Introduction: about 10 million people worldwide suffer from Chagas’ disease [1]. The World Health Organization (WHO) has explicitly acknowledged the significance of this condition and supports the use of Complementary and Alternative Medicine by health systems integrated with conventional treatments. Even so, one century after its discovery it still represents a global challenge [1,2]. Biotherapics are ultradiluted medicines and the infection of mice by Trypanosoma cruzi is an excellent model to understand their effect [3,4]. At 8 weeks, mice are physiologically more developed than at age 4 weeks, including a more competent immune system [5]. Aim: the aim of this study was to assess the effect of biotherapic of T. cruzi in dilution 17x on liver and spleen tissue of mice of different ages infected by this protozoon. Method: in a blind, randomized controlled trial 12 male Swiss mice aged 4 and 8 weeks, infected by 1,400 blood trypomastigotes T. cruzi Y strain were divided into groups control – treated with 7% hydroalcoholic solution (CI-4=3 animals or CI-8=3 animals) and treated with biotherapic 17x (BIOT-4=3 animals or BIOT-8=8 animals). Treatment (0.2 ml biotherapic/day/animal, per gavage) started after infection was verified (4th day) and animals were sacrificed on the 3rd day of treatment. For histopathological exam, the liver and spleen were removed and fixated in 4% paraformaldehyde for 24 hours and then processed for inclusion in paraffin. Semi-serial 7mm cuts were made and subjected to hematoxylin-eosin stain. It was performed a quantitative analysis of the number of nests of amastigotes and inflammatory foci in the liver. Slides were observed under microscope Olympus BX41 (Tokyo, Japan) and images captured with camera Qcolor3 (Olympus) coupled to the microscope. In the spleen it was counted the number of nests of amastigotes and the number of foreign-body giant cells. In each organ, 20 microscopic fields/cut were counted under power 40x totaling 120 fields/animal with microscope Olympus CBA (Tokyo, Japan). To analyze data it was used software Statistica 8.0. For data not exhibiting normal distribution it was used Kruskal-Wallis’ test at 5% significance and ANOVA for the ones with normal distribution. Chi-square test was used to compare percentages. Biotherapic 17d was prepared by adding 0.9 ml of blood with T. cruzi (10E+7 trypomastigotes/ml) to 9.1 ml of distilled water in laminar flow. Following dilutions were prepared in 86% hydroalcoholic solutions up to 16x. Dilution 17x was prepared with 7% hydroalcoholic solution [6]. It was performed microbiological control and in vivo biological risk of the biotherapic. Results showed a number of colony forming units proper for use (>1CFU/ml). Intraperitoenal inoculation of the biotherapic did not cause infection in animals. This study was approved by the Ethics Committee for Animal Experimentation/UEM protocol 030/2008. Results and Discussion: in the liver, animals of group BIOT-8 exhibited less nests of amastigotes (p

Probability Distribution of Repeatability of Industrial Robots

1991 ◽  
Vol 10 (3) ◽  
pp. 276-283 ◽  
Author(s):  
Einar Ramsli
Keyword(s):  
Normal Distribution ◽  
Normal Approximation ◽  
Industrial Robot ◽  
Industrial Robots ◽  
Frequency Function ◽  
Data Sets ◽  
Chi Square ◽  
Chi Square Test ◽  
Definition Of ◽  
Accuracy And Repeatability

The accuracy with which an industrial robot brings the load to a position and holds it there is perhaps the most important characteristic of an industrial robot. Many researchers have consequently been interested in this field during recent years. A common method for characterizing an industrial robot's ability to return to a position is to use the terms "accuracy" and "repeatability, " where accuracy characterizes the degree to which the actual measured value corresponds to a com manded value and repeatability the closeness of agreement between repeated measured values, under the same condi tions, to the same commanded value (ISO definitions). The normal approximation is regularly used when calculating the repeatability. A test on this assumption for six different industrial robots is reported in this article. Two approaches for this test are used: one looks at the shape of the frequency function for the repeatability figures measured, and the second uses a chi square test on the six data sets. The different tests show that there are small chances that the deviation of an industrial robot will follow a normal distribution. It seems to be a trend that the deviation has longer tails than the normal distribution. Simulation is used to elaborate on the consequences of the invalid assumption of normality in the definition of repeat ability. The conclusion is that it is reasonable to use the normal approximation when there is no strong evidence that the deviation distribution is negatively skewed.

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