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Search Results: 1 - 10 of 2545 matches for " Descriptive Statistics "
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Spatial variability of soil salinity of the perimeter irrigated Engenheiro Arcoverde of Condado, Paraiba State
Armindo Bezerra Le?o,Lúcia Helena Garófalo Chaves,Iêde de Brito Chaves,Hugo Orlando Carvallo Guerra
Engenharia Ambiental : Pesquisa e Tecnologia , 2009,
Abstract: Knowledge of spatial variation of soil attributes may contribute to the planning of commercial agriculture aiming at precision agriculture. The objective of this work was to study the spatial variability of electrical conductivity of saturation extract (ECse), potential ionic hydrogen in the saturated soil (pHse) and the exchangeable sodium percentage (ESP) of a Fluvic Neossol, in the Irrigated Perimeter Engenheiro Arcoverde, district of Condado-PB, Brazil. Soil samples were collected in a irregular grid with a spacing of 100 m, at layers depth of 0 to 0.20 m, 0.20 to 0.40 m and 0.40 to 0.60. The data was analyzed with descriptive statistics and geostatistics, by fitting semivariogram models. It was observed high coefficient of variation for ECse and ESP and low for pHse; these coefficients decreased with increasing depth. The exponential and spherical models were fitted to CEes and PST and exponential model for pHes. The ECse and ESP presented from weak to moderate spatial dependence and pHse a weak spatial dependence, ranging from 45 to 1.301 m for CEes; 61 to 1.431 m for PST and 30 to 80 m for pHes.
Some morphological features of carp (Cyprinus carpio Linnaeus, 1758) in different stages of development
M. Oana Arteni,Irina Ro?ca
Animal Biology & Animal Husbandry , 2010,
Abstract: The present paper investigates some representative morphological characters (total length,standard length, head width, maximum body width, body girth and body weight) of carp (Cyprinuscarpio) during three stages of development (one, two, and three summer old). Biometric analyses wasperformed on 70 individuals for each age from Fish Farm Tig na i, Ia i County. Morphological characterswere statistically processed and the measurements revealed new data regarding the characterstics of theexamined population. This population of carp may be considered as homogeneous.
Against coefficient of variation for estimation of intraindividual variability with accuracy measures
Philippe Golay,Delphine Fagot,Thierry Lecerf
Tutorials in Quantitative Methods for Psychology , 2013,
Abstract: Previous studies have shown that intraindividual variability (iV) in performance is an important indicator of individual s cognitive functioning and neurological integrity. While most experiments have examined iV of performance using Reaction Time data (RTs), few studies have considered it with accuracy measures (e.g. number or percentage of correct responses). For these two types of measures, intraindividual standard deviation (iSD) or intraindividual coefficient of variation (iCV; intraindividual standard deviation divided by the individual mean) were used as indicators of iV in performance. However, because accuracy data have a lower and an upper bound (in contrast to RTs), we illustrate both formally and with simulated data, that the iCV cannot be used with accuracy measures. We also show that the coefficient iCV is influenced by the number of items which is an issue when dealing with missing data. We further provide formulas that may help researchers to visualize and correctly interpret their data using any spreadsheet software. The current article finally proposes an alternative coefficient (zeta) to examine iV in performance with accuracy measures that shows similar behaviour as does iCV with RTs data.
The use of Statistical Methods in Mechanical Engineering
Iram Saleem,Muhammad Aslam,Muhammad Azam
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: Statistics is an important tool to handle the vast data of present era as statistics can interpret all the information in such a beauty that so many conclusions can be extracted from it. The aim of this study is to see the use of statistical methods in Mechanical Engineering (ME) therefore; we selected research papers published in 2010 from the well reputed journals in ME under Taylor and Francis Company LTD. More than 350 research papers were downloaded from well reputed ME journals such as Inverse Problem in Science and Engineering (IPSE), Machining Science and Technology (MST), Materials and Manufacturing Processes (MMP), Particulate Science and Technology (PST) and Research in Nondestructive Evaluation (RNE). We recorded the statistical techniques/methods used in each research paper. In this study, we presented frequency distribution of descriptive statistics and advance level statistical methods used in five of the ME journals in 2010.
Maternity Benefit Practices at NGOs in Bangladesh: Laws and Implementation  [PDF]
Omar Faroque, Md. Rafiqul Islam, Md. Obaidur Rahman, Md. Mominul Islam
Beijing Law Review (BLR) , 2013, DOI: 10.4236/blr.2013.44021
Abstract:

Maternity leave is an important benefit to the female employees and it plays important role to increase organizational loyalty, efficiency and job satisfaction, particularly in the Non-Government Organizations (NGOs). The objective of the study is to assess the laws and implementation of the maternity benefits at the diverse NGOs on different working echelon inBangladesh. Descriptive statistics and zero order correlation method have been performed using the data haul out from one hundred female employees experiencing at least one child at the different NGOs inKurigram District,Bangladesh. Among all female employees, salary structure and the managerial position are not satisfactory at NGOs in Bangladesh, although higher education of females plays an important role to get the job. In case of maternity benefits, all of them have got three or four months as maternity leave period and a significant number have not got any types of payment during maternity leave (27%), have not enjoyed maternity leave properly (24%), and have been terminated, sent away or expelled etc. due to maternity leave (19%). In addition, an inverse relation of duration of maternity leave with age (26.4%) and length of service (34.1%) has also been identified i.e., duration of maternity leave decreases with increasing employees’ age and length of services. In our study, evidently there are no NGO practices laws of maternity benefit properly in Bangladesh. Therefore, every NGO should administer and implement the Laws of maternity benefit properly.

O analiz a statisticilor utilizate n comunic rile tiintifice psihologice
Marian Popa
Psihologia Resurselor Umane , 2009,
Abstract: This article analyses the statistical procedures used in the proceedings of the one of the psychology conferences regularly organized in Romania. 111 papers in six branches of applied psychology were scrutinized. The analysis was structured on descriptive statistics (numerical and graphical), and inferential statistics (parametric and nonparametric). Was also pursued the extent to which papers complied with APA recommendations on the reporting of confidence limits and size effect. Results: 64.9% of the papers reported statistical results. The sections with more statistical based papers are military psychology (85.7%) and industrial-organizational psychology (84%). On the other hand, only 52.4% papers on educational psychology reported statistics procedures. The average of the reported samples was 190 subjects (minimum 10, maximum 1519). A percentage of 26.4% of works includes at least one statistical descriptive indicator, while 31.9% of works containing statistics, have no descriptive indicators. The graphics used are mostly bar and pie. Regarding inferential statistics, 47.2% of work contains at least one statistical test, and 36.1% have none statistical test. The most frequent utilized tests are Pearson r and t tests. It was recorded no single case of reporting effect sizes and confidence limits. Conclusions: The results allow us to appreciate that the papers presented at scientific events, most of them by young psychologists, contain a relative insufficiently matured statistical analysis, and often insufficient connected to the problem studied. We must appreciate, however, as positive the interest in empirical research and statistical analysis of results.
An analysis of distribution transformer failure using the statistical package for the social sciences (SPSS) software
Mago,M. G; Valles,L; J.Olaya,J;
Ingeniería e Investigación , 2012,
Abstract: a methodology was developed for analysing faults in distribution transformers using the statistical package for social sciences (spss); it consisted of organising and creating of database regarding failed equipment, incorporating such data into the processing programme and converting all the information into numerical variables to be processed, thereby obtaining descriptive statistics and enabling factor and discriminant analysis. the research was based on information provided by companies in areas served by corpoelec (valencia, venezuela) and codensa (bogotá, colombia).
Caracteriza??o das queimadas acidentais em campo, no Município de Santa Maria-RS
Jacobi, Luciane Flores;Lúcio, Alessandro Dal'Col;Storck, Lindolfo;Lopes, Sidinei José;Cargnelutti Filho, Alberto;
Ciência Rural , 2009, DOI: 10.1590/S0103-84782009000300042
Abstract: the objetive of this research was to conduct a study on accidental field burns in the county of santa maria-rs, brazil to identify and characterize sites where they most frequently occur with the objective of helping in the planning and controlling of those burns. the variable of interest was the number of daily calls received by the santa maria fire department, from january 1st 1993 to december 31st 2004. it was observed that the fire department received on average 1.81 daily calls; that the calls were followed by a dry period of four days, on average; and most calls occurred during the afternoon and alongside the almost unhabited rs 287 highway. the month with the highest number of calls was august, and the year 1999 presented the highest occurrence number of field burns. finally, the number of calls was equally distributed along the weekdays. the margins of the highways and the following city districts: distrito industrial, medianeira, itararé, tomazzetti and parque pinheiro machado presented the highest chances of burnings occurrence.
Mortalidade por homicídios no Brasil na década de 90: o papel das armas de fogo
Peres,Maria Fernanda Tourinho; Santos,Patrícia Carla dos;
Revista de Saúde Pública , 2005, DOI: 10.1590/S0034-89102005000100008
Abstract: objective: to describe the growth of homicide death in brazil and to investigate the contribution of firearms to homicide death growth in the 90s. methods: an ecological descriptive time series was carried out for the period 1991 to 2000. external cause mortality data were obtained according to place of residence for the overall population and by gender from the ministry of health mortality information system. homicides were classified as firearm, non-firearm and unknown (weapon) deaths. proportional mortality and mortality rates (by 100,000) were calculated. results: homicides accounted for 33% of all external cause deaths in the 90s. firearms were used in more than 50% of deaths in 1991 and in almost 70% in 2000. this growth was seen for both genders and in all state capitals. homicide mortality rate grew 27.5% in the whole country, and firearm homicide mortality rate grew 72.5%. during the same period there was a drop in deaths classified as unknown weapon homicide, which could partially explain the growth seen in firearm homicide rates. conclusions: data suggest the magnitude of firearm contribution for the growing tendency of homicide deaths in brazil in the 90s. data quality regarding intentionality and type of weapon used has hindered data analysis.
Heterogeneidade dos pontos experimentais de curvas de reten??o da água no solo
Moraes, S.O.;Libardi, P.L.;Reichardt, K.;Bacchi, O.O.S.;
Scientia Agricola , 1993, DOI: 10.1590/S0103-90161993000300011
Abstract: in an area of "terra roxa estruturada latossólica" (rhodic kanhapludalf), in piracicaba, sp, brazil (20° 42' 30" s, 47° 38' 00" w, 576 m), 250 undisturbed soil samples were collected at 25 cm soil depth, according to a regular grid of spacing of 5 m, resulting a network of 25 unes and 10 columns. these samples were used to determine 250 soil water retention curves each one with eigth experimental points, using haines funnels (tensions of 5xl02, 1x103, 6x103 and 1x104 pa) and richards pressure chambers (pressures of 3x104, 8x104,3x105 and 1x106 pa), totalizing two thousand values. position measurements (mode, median and arithmetic mean), variability (total amplitude, interquartil amplitude, standard deviation, coefficient of variation, assimetry, kurtosis and confident limits around the mean) and number of samples to estimate the mean of the soil water content at a specific probability level, were used with the following objectives: a) to verify how close to the normal distribution are the values of soil water content for the different considered tensions and hence, to investigate what is the best position measurement; b) to quantify the variability in each considered tension, identifying the most problematic in the study of soil-water retention and also to analyse the measurement sensibility through the calculation of the necessary number of samples to estimate the mean (assuming a spatial independence of the samples). from the analysis of the obtained results, it could be concluded that the soil-water content values corresponding to tensions of 5x102 and 1x103 pa showed very skewed distributions, so that care should be taken in using the arithmetic mean as a position measurement. the neglection of problem-samples, based on the physical analyses of results, allowed a better aproximation to the normal distributions for these tensions, indicating that a complete soil-water retention curve should always be prefered in the place of only two or three points of restricted
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