Comparing Performance II: Parametric and Non-Parametric Analyses

SummaryLight transmission platelet aggregation tests are important for diagnosing platelet function defects. However, uncertainties exist about the best procedures to determine aggregation reference intervals. We investigated methods for determining reference intervals for light transmission aggregation tests, using the % maximal aggregation values for prospectively collected data on healthy control samples. Reference intervals for samples tested at 250 x 109 platelets/l were determined by mean ± 2 standard deviations and non-parametric analyses. To establish reference intervals for tests on thrombocytopenic subjects, regression analyses were used to estimate 95% confidence limits for % maximal aggregation, according to sample platelet counts, using data for control samples diluted to match the platelet count of undiluted thrombocytopenic patient platelet-rich plasma samples. For samples tested at 250 x 109 platelets/l, non-parametric analyses described 95% of data for healthy control samples better than mean ± 2 standard deviations. For samples tested at lower counts, to match thrombocytopenic samples, the % maximal aggregation was influenced by platelet count and derived limits were wider at very low platelet counts for almost all agonists. With ristocetin, it proved feasible to test samples with very low platelet counts to exclude Bernard-Soulier syndrome and type 2B von Willebrand disease. Non-parametric analyses should be the preferred method to establish light transmission aggregation reference intervals for samples tested at normal platelet counts. The derived limits for thrombocytopenic samples provide guidance for evaluating thrombocytopenic platelet function disorders, including which agonists to test, based on the sample platelet count.

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Linkage of Crohn’s disease to the major histocompatibility complex region is detected by multiple non-parametric analyses

Gut ◽

10.1136/gut.44.4.519 ◽

1999 ◽

Vol 44 (4) ◽

pp. 519-526 ◽

Cited By ~ 71

Author(s):

H Yang ◽

S E Plevy ◽

K Taylor ◽

D Tyan ◽

N Fischel-Ghodsian ◽

...

Keyword(s):

Crohn’S Disease ◽

Crohn's Disease ◽

Linear Regression Analysis ◽

Hla Antigens ◽

Significance Level ◽

Affected Relative ◽

Parametric Analyses ◽

Sib Pairs ◽

Jewish Families ◽

Non Parametric

BACKGROUNDThere is evidence for genetic susceptibility to Crohn’s disease, and a tentative association with tumour necrosis factor (TNF) and HLA class II alleles.AIMSTo examine the potential of genetic linkage between Crohn’s disease and the MHC region on chromosome 6p.METHODSTNF microsatellite markers and, for some families, additional HLA antigens were typed for 323 individuals from 49 Crohn’s disease multiplex families to generate informative haplotypes. Non-parametric linkage analysis methods, including sib pair and affected relative pair methods, were used.RESULTSIncreased sharing of haplotypes was observed in affected sib pairs: 92% (48/52) shared one or two haplotypes versus an expected 75% if linkage did not exist (p=0.004). After other affected relative pairs were included, the significance level reached 0.001. The mean proportion of haplotype sharing was increased for both concordant affected (π=0.60, p=0.002) and unaffected sib pairs (π=0.58, p=0.031) compared with the expected value (π=0.5). In contrast, sharing in discordant sib pairs was significantly decreased (π=0.42, p=0.007). Linear regression analysis using all three types of sib pairs yielded a slope of −0.38 at p=0.00003. It seemed that the HLA effect was stronger in non-Jewish families than in Jewish families.CONCLUSIONSAll available analytical methods support linkage of Crohn’s disease to the MHC region in these Crohn’s disease families. This region is estimated to contribute approximately 10–33% of the total genetic risk to Crohn’s disease.

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The Value of H0 from Gaussian Processes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314013751 ◽

2014 ◽

Vol 10 (S306) ◽

pp. 25-27 ◽

Cited By ~ 6

Author(s):

Vinicius C. Busti ◽

Chris Clarkson ◽

Marina Seikel

Keyword(s):

Gaussian Processes ◽

Covariance Function ◽

Parametric Method ◽

Hubble Constant ◽

Covariance Functions ◽

Λcdm Model ◽

Parametric Analyses ◽

Non Parametric

AbstractA new non-parametric method based on Gaussian Processes (GP) was proposed recently to measure the Hubble constant H0. The freedom in this approach comes in the chosen covariance function, which determines how smooth the process is and how nearby points are correlated. We perform coverage tests with a thousand mock samples within the ΛCDM model in order to determine what covariance function provides the least biased results. The function Matérn(5/2) is the best with sligthly higher errors than other covariance functions, although much more stable when compared to standard parametric analyses.

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Geophysical Variables and Behavior: XLIV. Days of Subjective Precognitive Experiences and the Days before the Actual Events Display Correlated Geomagnetic Activity

Perceptual and Motor Skills ◽

10.2466/pms.1987.65.1.173 ◽

1987 ◽

Vol 65 (1) ◽

pp. 173-174

Author(s):

Douglas R. Lewicki ◽

George H. Schaut ◽

Michael A. Persinger

Keyword(s):

Data Base ◽

Geomagnetic Activity ◽

Published Data ◽

Temporal Perception ◽

Methodological Criterion ◽

Actual Event ◽

Parametric Analyses ◽

And Behavior ◽

Non Parametric

Precognitive experiences concerning consequent events have been hypothesized to be alterations in temporal perception. All such experiences ( n = 156) that contained the days, months and years for the experience and the event were included from a published data base. Only 40 cases met the methodological criterion of having a temporal discrepancy between the experience and the event of equal to or more than 4 days. For two subsamples (discrepancies of 4–14 days and 15 to 2,000 days), both parametric and non-parametric analyses showed intermediate strength (0.50) correlations between the global geomagnetic activity on the day of the experience and the activity that would occur during the two days before the actual event.

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Quantitative analysis of time-series fluorescence microscopy using a spot tracking method: application to Min protein dynamics

Biologia ◽

10.2478/s11756-009-0013-y ◽

2009 ◽

Vol 64 (1) ◽

Cited By ~ 7

Author(s):

Somrit Unai ◽

Paisan Kanthang ◽

Udorn Junthon ◽

Waipot Ngamsaad ◽

Wannapong Triampo ◽

...

Keyword(s):

Fluorescent Protein ◽

Leading Edge ◽

Polar Zone ◽

E Coli ◽

Particle Ensemble ◽

Dynamic Exponent ◽

Parametric Analyses ◽

Green Fluorescent ◽

The Mind ◽

Non Parametric

AbstractThe dynamics of MinD protein has been recognized as playing an important role in the accurate positioning of the septum during cell division. In this work, spot tracking technique (STT) was applied to track the motion and quantitatively characterize the dynamic behavior of green fluorescent protein-labeled MinD (GFP-MinD) in an Escherichia coli system. We investigated MinD dynamics on the level of particle ensemble or cluster focusing on the position and motion of the maximum in the spatial distribution of MinD proteins. The main results are twofold: (i) a demonstration of how STT could be an acceptable tool for MinD dynamics studies; and (ii) quantitative findings with parametric and non-parametric analyses. Specifically, experimental data monitored from the dividing E. coli cells (typically 4.98 ± 0.75 µm in length) has demonstrated a fast oscillation of the MinD protein between the two poles, with an average period of 54.6 ± 8.6 s. Observations of the oscillating trajectory and velocity show a trapping or localized behavior of MinD around the polar zone, with average localization velocity of 0.29 ± 0.06 µm/s; and flight switching was observed at the pole-to-pole leading edge, with an average switching velocity of 2.95 ± 0.31 µm/s. Subdiffusive motion of MinD proteins at the polar zone was found and investigated with the dynamic exponent, α of 0.34 ± 0.16. To compare with the Gaussian-based analysis, non-parametric statistical analysis and noise consideration were also performed.

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Non-parametric analyses of efficiency of airports

Transportation Planning and Technology ◽

10.1080/03081060.2014.921406 ◽

2014 ◽

Vol 37 (6) ◽

pp. 539-553 ◽

Cited By ~ 1

Author(s):

Hsu-Hao Yang ◽

Yen-Sheng Huang

Keyword(s):

Parametric Analyses ◽

Non Parametric

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The Impact of Quality Management on Profitability: An Empirical Study

Journal of Operations and Supply Chain Management ◽

10.12660/joscmv1n1p66-77 ◽

2008 ◽

Vol 1 (1) ◽

pp. 66 ◽

Cited By ~ 3

Author(s):

Alexandre Pignanelli ◽

João Mário Csillag

Keyword(s):

Quality Management ◽

Empirical Study ◽

National Quality ◽

Quality Award ◽

Parametric Analyses ◽

The Impact ◽

National Quality Award ◽

Non Parametric

The article investigates the impact of quality on profitability, following the evolution duringa ten years period of 31 firms recognized by Brazilian National Quality Award (PNQ). Data of other companiesfrom the same sectors were also considered, reaching 5354 observations. The statistical analysesincluded regressions, parametric and non-parametric analyses.

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