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Young drivers among the group recorded highest fatalities index in road traffic crashes. The objective of this study was to identify factors affecting injury severity of young drivers using 5-years crash data (2008-2012) in Sabah, Malaysia. This study used a combination of parametric and non-parametric analysis to allows the specification of nonlinearities and interactions in addition to main effects. The results indicate that crashes on nighttime, federal roads and involved with a single-vehicle are positively associated with injury among young drivers. Interestingly, municipal roads, female drivers, crashes on the roundabout and T/Y junction are less likely to involve injury. A higher-order interaction suggests that not-at-fault young drivers involved with out-of-control or hit the object are more likely to be severe. On the other hand, young passenger car drivers involved in overturn and sideswipe collisions are negatively associated with the injury. It was also found that young drivers with driving too close behaviour are less likely to injure when involved in rear-end collisions for passenger car and four-wheel drive. Findings of this study will help relate authorities to design well-targeted restrictive measures in reducing the severity level of young drivers in traffic crashes.

Multiple myeloma (MM) is a type of cancer that remains incurable. In the last decade, most research into MM has focused on investigating the improvement in the therapeutic strategy. Our study assesses the survival probability of 48 patients diagnosed with MM based on parametric and non-parametric techniques. We performed parametric survival analysis and found a well-def- ined probability distribution of the survival time to follow three-parameter lognormal. We then estimated the survival probability and compared it with the commonly used non-parametric Kaplan-Meier survival analysis of the survival times. The comparison of the survival probability estimates of the two methods revealed a better survival probability estimate by the parametric method than the Kaplan-Meier. The parametric survival analysis is more robust and efficient because it is based on a well-defined parametric probabilistic distribution, hence preferred over the non-parametric Kaplan-Meier. This study offers therapeutic significance for further enhancement in the treatment strategy of multiple myeloma cancer.

Limited sample sizes imply parametric assumptions could be violated, even if traits have been reported to fulfil parametric assumptions. Parametric studies have addressed a non-significant influence of CSN1S1 genes on Murciano-Granadina milk yield, fat, protein and dry extract. We used non-parametric categorical tests to find alternative statistical methods to analyse the power to explain the variability found in the population regarding milk yield and its components. We analysed 2090 records for milk yield, and its components from 710 Murciano-Granadina CSN1S1-genotyped goats. Categorical regression equations were issued to predict which and at what level these factors may determine milk yield (kg), fat (kg), protein (kg) and dry extract (kg). All environmental (farm and parturition year) and animal-inherent factors (genotype, birth type and age) resulted statistically significant (p

Recurrent event data often arise in longitudinal studies. In many applications, subjects may experience two different types of events alternatively over time or a pair of subjects may experience recurrent events of the same type. Medical advances have made it possible for some patients to be cured such that the disease of interest does not recur. In this article, we consider non parametric analysis of bivariate recurrent event data with cure fraction. Using the inverse-probability weighted (IPW) approach, we propose non parametric estimators for the proportion of cured patients and for the joint distribution functions of bivariate recurrence times of the uncured ones. The asymptotic properties of the proposed estimators are established. Simulation study indicates that the proposed estimators perform well in finite samples.

Recently, with increasingly concern on energy and environmental problems, China’s new programs of energy intensity reduction were released in 11th&12th Five-Year-Plan, which results in an urgent need for regional energy intensity reduction potential evaluation. Based upon this recognition, this study mainly focuses on China’s regional energy intensity reduction potential, by employing global data envelopment analysis approach. Moreover, investigating the sources of energy intensity reduction potential change with index decomposition analysis is also one of our targets. The results show that: (1) in the sample period, the energy intensity reduction potential of the western regions is significantly higher than that of central and eastern regions, and the eastern regions have the lowest energy intensity reduction potential. (2) The energy intensity of the eastern regions can be reduced approximately 10–20%, whereas that of the western region can be reduced 30–45%, and that of the whole country can be reduce 25–30% on current basis. (3) According to the sources of energy intensity reduction potential change, it can be found that the energy intensity reduction potential of eastern areas decreased over the sample period. Both the increasing technical efficiency and technical progress contribute to the decline of energy intensity reduction potential. But the western region’s energy intensity reduction potential presents an upward trend during 2000–2011, and the technical regression is the main reason. Therefore, the western regions should pay more attention on optimizing the production technology.

The purpose of this study is to analyze the implementation level of introduce technology of bokashi on rice cultivation. This study was conducted in the village Kuripan Sub Penengahan, South Lampung regency. Technique of data collecting conducted by field observation and interview by using of quizioner. Determine of sample conducted with purposive sampling. Data analysed using non parametric analysis (rating scale ) . Result of the study relevead that the public interest of farmer very high to bokashi applying. Based to result of evaluation about perception of farmer to technology of making and applying of bokashi in rice cultivation, applying has 72,0% high respons and 28,0% do not respons. Keywords: f armer , perception , bokashi, rice

The validity and usefulness of empirical data requires that the data analyst ascertains the cleanliness of the collected data before any statistical analysis commence. In this study, petroleum demand data for a period of 24 hours was collected from 1515 households in 10 clusters. The primary sampling units were stratified into three economic classes of which 50% were drawn from low class, 28% from medium class and 22% from high class. 63.6% of the questionnaires were completed whereas incomplete data was computed using multivariate imputation by chained equation with the aid of auxiliary information from past survey. The proportion of missing data and its pattern was ascertained. The study assumed that missing data was at random. Nonparametric methods namely Nadaraya Watson, Local Polynomial and a design estimator Horvitz Thompson were fitted to aid in the estimation of the total demand for petroleum which has no close substitute. The performance of the three estimators were compared and the study found that the Local Polynomial approach appeared to be more efficient and competitive with low bias. Local polynomial estimator took care of the boundary bias better as compared to Nadaraya Watson and Horvitz Thompson estimators. The results were used to estimate the long time gaps in petroleum demand in Nairobi county, Kenya.

Evaluation of the conditions of Jalan Soekarno Hatta using PCI method shows that the condition of "Good" both on rigid and flexible pavement is most common, with the percentage of each of them being 61.9% and 21.6%. Meanwhile, by using PSI method, the most commonly found are "Fair" conditions both in rigid and flexible pavement, with the percentage of each being 81% and 48,9%. Using the SDI method on the flexible pavement, the most commonly found is the condition of "Medium" with a percentage of 65,9%. The parametric analysis between PCI and PSI on rigid pavement produced R 2 = 0.0548 with a regression equation of PCI = 96,66 – 3,9352 x PSI, while PCI and PSI correlation on flexible pavement produced R 2 = 0.8163 with regression equation of PCI = 27,673 + 16,848 x PSI., and PCI and SDI correlations on flexible pavement yields R 2 = 0,8653 with a regression equation of PCI = 94,663 – 0,4462 x SDI The non-parametric analysis between PCI and PSI on rigid pavement produced a correlation coefficient of 0.043, while the PCI and PSI values on flexible pavements produced a correlation coefficient of 0.397, and PCI and SDI on flexible pavement produced a correlation coefficient of 0.492. Based on the two methods, both parametric and non parametric analysis, the relationship between PCI and SDI was considered better than the PCI and PSI relationship because it produced an R 2 value and a greater correlation coefficient Evaluasi kondisi Jalan Soekarno Hatta dengan menggunakan metode PCI menunjukan bahwa yang paling banyak di temukan adalah kondisi “Good” baik pada perkerasan kaku maupun perkerasan lentur, dengan persentase masing masing adalah 61,9 % dan 21,6 %. Sedangkan dengan menggunakan metode PSI yang paling banyak di temukan adalah kondisi “Fair” baik pada perkerasan kaku maupun perkerasan lentur, dengan persentase masingmasing adalah 81 % dan 48,9 %. Dengan menggunakan metode SDI pada perkerasan lentur yang paling sering di temukan adalah kondisi “Sedang” dengan persentase 65,9 %. Analisis parametrik antara PCI dan PSI pada perkerasan kaku menghasilkan nilai R2= 0,0548 dengan persamaan regresi yaitu PCI= 96,66 – 3,9352 x PSI, sedangkan korelasi PCI dan PSI pada perkerasan lentur menghasilkan nilai R2= 0,8163 dengan persamaan regresi yaitu PCI = 27,673 + 16,848 x PSI, dan korelasi PCI dan SDI pada perkerasan lentur menghasilkan nilai R2= 0,8653 dengan persamaan regresi yaitu PCI = 94,663 – 0,4462 x SDI. Analisis non parametrik antara PCI dan PSI pada perkerasan kaku menghasilkan nilai koefisien korelasi sebesar 0,043, sedangkan nilai PCI dan PSI pada perkerasan lentur menghasilkan nilai koefisien korelasi sebesar 0,397, dan nilai PCI dan SDI pada perkerasan lentur menghasilkan nilai koefisien korelasi sebesar 0,492. Berdasarkan kedua metode analisis baik analisis parametrik maupun non parametrik hubungan PCI dan SDI dinilai lebih baik dibandingkan hubungan PCI dan PSI karena menghasilkan nilai R2 dan koefisien korelasi yang lebih besar.

This article paves a way for assessing flood risk by the use of two-parameter distributions, for the intervals between threshold exceedences rather than by the traditional exponential distribution. In a case study, the apparent properties of intervals between exceedences of runoff events differ from those anticipated for exponentially distributed series. A procedure is proposed to relate two statistical parameters of the intervals to threshold discharges. It considers partial duration series (PDS) with thresholds equal to all high enough observed discharges. To avoid unnecessary assumptions on the behaviour of those parameters and effects of dependence between parameters for different PDS, a non-parametric trend-free pre-whitened scheme is applied. It leads to power-law relationships between a discharge and the mean and standard deviation of the intervals between its exceedences. Predicted mean inter-exceedence intervals, for the highest observed discharges at the stations, are closer to the obse...

This paper examines the technical efficiency of wheat farms in Bangladesh using cross-sectional farm level data and secondary time series data from a sample of 150 farms in the region of Khulna division, Bangladesh. To sharpen the efficiency estimates, the authors use window analysis, slacks variable analysis and data envelopment analysis (DEA) assuming constant and variable returns to scale with the application of input-orientation approaches. The estimated overall efficiency measures were regressed on the socioeconomic characteristics of the farmers to identify factors influencing the technical efficiency of wheat farms through Tobit analysis.

Two-treatment multicentre clinical trials are very common in practice. In cases where a non-parametric analysis is appropriate, a rank-sum test for grouped data called the van Elteren test can be applied. As an alternative approach, one may apply a combination test such as Fisher's combination test or the inverse normal combination test (also called Liptak's method) in order to combine centre-specific P-values. If there are no ties and no differences between centres with regard to the groups’ sample sizes, the inverse normal combination test using centre-specific Wilcoxon rank-sum tests is equivalent to the van Elteren test. In this paper, the van Elteren test is compared with Fisher's combination test based on Wilcoxon rank-sum tests. Data from two multicentre trials as well as simulated data indicate that Fisher's combination of P-values is more powerful than the van Elteren test in realistic scenarios, i.e. when there are large differences between the centres’ P-values, some quantitative interaction be...

In the comment on Ruefli and Wiggins (2003), a number of points are made supporting the variance component analysis approach to determining the importance of industry, corporate, and business segment factors on business segment performance. This response addresses in more detail the nature of the methodological and statistical assumptions made by variance components analysis or ANOVA and their implications for the ‘puzzling’ results obtained when these techniques are employed. The response then contrasts the variance-based methodologies with a non-parametric approach used in Ruefli and Wiggins (2003) that makes fewer and weaker assumptions and yields more robust and more internally consistent results. The response also examines the limitations of employing an autoregressive approach to measuring persistence of abnormal profits and contrasts it with a non-parametric methodology presented in the article. Copyright © 2005 John Wiley & Sons, Ltd.

After a brief review of the literature, two non-parametric tests for homogeneity of variances are presented. The first test is based on the analysis of means for ranks, which is a non-parametric version of the analysis of means (ANOM) that uses ranks as input for an ANOM test. The second test uses inverse normal scores of the ranks of scale transformations of the observations as input to the ANOM. Both homogeneity of variances tests can be presented in a graphical form, which makes it easy for practitioners to assess the practical and the statistical significance. A Monte Carlo study is used to show that these tests have power comparable with that of well-known robust tests for homogeneity of variances.

Lewbel's composite model for comparing the AIDS and Translog demand systems is estimated using Italian meat-consumption data. Preliminary non-parametric diagnoses suggest that exogenous shifters of price and expenditure need not be introduced into a parametric model. By contrast, the parametric analysis demonstrates that demographic shifters can account for substantial changes in patterns of meat consumption. Although a parametric model without demographic variables performs adequately, likelihood ratio tests substantiate that an AIDS model with demographic variables performs even better. Copyright 1994 by Oxford University Press.

A methodological framework for simulating real-like HRV during stress test with controlled spectral properties has been developed with the purpose to assess SPWVD and time-variant AR analysis. For each method results have been evaluated computing the estimation error for LF and HF components during all the test (mean error of the order of 10% in all case) and a direct comparison based on the correlation between estimate and original ACF yields very high values (rhoWV=0, 99 and rhoAR=0, 94). In real data analysis bothmethods highlightan inversion of the relative spectral balance around the apex of exercise which passes from LF to HF prevalence.

We consider how one might test observed choice data for consistency with optimizing models in the presence of measurement error. We derive an appropriate test statistic and conduct case study involving cost minimization behavior by electric utility plants.

A non-parametric method for evaluating the results of recognition memory experiments and psychophysical detection experiments is presented. The method is based upon an ordinal analysis of recognition performance, which transforms the results of recognition tests into equivalent results for a forced-choice experiment.