Paired Samples T-Test

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Experimentation and t-Test of Viscoelastic Vibration Damping

Experimentation and t-Test of Viscoelastic Vibration Damping

t-test is based on t-distribution and is considered an appropriate test for judging the significance of a sample mean or for judging the significance of difference between the means of two samples in case of small sample(s) when population variance is not known (in which case we use variance of the sample as an estimate of the population variance). In case two samples are related, we use paired t-test(or what is known as difference test) for judging the significance of the mean of difference between the two related
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Investigation of the Effects of Air Conditioning System on the Temperature and Speed of Automobile Engine Using Paired T Test and Regression Analysis

Investigation of the Effects of Air Conditioning System on the Temperature and Speed of Automobile Engine Using Paired T Test and Regression Analysis

nents of the equation were gotten from Equations (4) and (5). The pair t-test was used because of the related samples and small sample size in line with the litera- ture [10]. The calculated value of t-statistics after estimated was compared to the critical value of t-statistics at the degrees of freedom ( n − 1) to ascertain if the A/C system has an effect of increasing temperature of the internal combustion engine.

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Tests for paired count outcomes

Tests for paired count outcomes

If a test performs correctly, it should yield type I error rates at the specified nominal level α = 0.05 . Several factors can affect the performance of the test. First, if data do not follow the assumed mathematical distribu- tions, the test in general is biased. For example, if the paired t-test is applied to paired outcomes that are not bivariate normal, it will generally be biased. Second, with the exception of the paired t-test, all tests discussed above rely on large samples to provide valid results. When applied to small or moderate samples, such tests may have bias. For example, the normal distribution may not provide a good approximation to the sampling distribution of the statistic U n of the Wilcoxon signed-
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A New Maximum Test via the Dependent Samples t Test and the Wilcoxon Signed Ranks Test

A New Maximum Test via the Dependent Samples t Test and the Wilcoxon Signed Ranks Test

The maximum test’s critical values were systematically lower than the Bonferroni-Dunn test and therefore the more powerful test, and were systematically larger than critical values for the t-test which controls the inflation of Experiment-Wise Type I errors when conducting both the dependent samples t and Wilcoxon signed-ranks test. The maximum test eliminates the need to make a forced choice between the dependent sample t-test and the WSR test when the distribution from which samples are drawn remain unknown, or are known to be non-normally distributed. The test permits the safe application of both the classical and non-parametric tests with the maximum of the two referred to the new table of critical values that are designed to maintain the Type I error rate to nominal α while guaranteeing the maximum power of the two tests. The maximum test also renders the Bonferroni-Dunn adjustment method unnecessary.
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Parameter variation in the "log t" convergence test

Parameter variation in the "log t" convergence test

This paper estimates a local linear version of the model used in Phillips and Sul's (2007, 2009) "log t" convergence test. It documents the economically and statistically significant within-sample variation in the estimated value of the key parameter of that test when applied to data for 18 OECD countries during the 20th century. This variation suggests the substantial waxing and waning of the forces driving convergence, possibly due to low-frequency shocks and changes in the level economic integration.

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Two-Component Cluster Analysis of a Large Serodiagnostic Database for Specificity of Increases of IgG Antibodies against Pertussis Toxin in Paired Serum Samples and of Absolute Values in Single Serum Samples

Two-Component Cluster Analysis of a Large Serodiagnostic Database for Specificity of Increases of IgG Antibodies against Pertussis Toxin in Paired Serum Samples and of Absolute Values in Single Serum Samples

2.8- and 3.3-fold increases. In subgroups of paired sera with rela- tively high IgG-Ptx values in the first serum sample, the distinc- tion between the cluster with low reactivity and the cluster with high reactivity was less sharp and optimum cutoffs were lower. This is probably due to contamination with patients with pertus- sis, in whom the IgG-Ptx already or almost had reached its peak so that a further increase was absent or modest. The results in the various subgroups may be translated in the following diagnostic rule: IgG-Ptx increases in paired sera are diagnostic for actual pertussis when the increase is ⱖ3-fold to a level of at least 20 IU/ml or ⱖ 2-fold to a level of ⬎ 100 IU/ml.
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Goodness-of-t test for multistable Lévy processes

Goodness-of-t test for multistable Lévy processes

The multistable processes are extensions of stable processes, where the index of stability is replaced by a function ranging in (0, 2) . The aim of this article is to build a statistical test which is able to detect a multistable behavior of a process belonging to the class of the multistable Lévy processes. The properties are stated for a discrete observation scheme of one trajectory.

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A Modified T-Test for Football Referees to Test Agility, Quickness and Sprint Performances

A Modified T-Test for Football Referees to Test Agility, Quickness and Sprint Performances

The football referees perform many actions as jogging, running, sprinting, side steps and backward steps during a football match. Further, the football referees change match activities every 5-6 seconds. Many tests are being conducted to determine the physical levels and competences of football referees like 50 m running, 200 m running, 12 minutes Cooper test, 6 × 40 m etc. All of these tests include straight runnings dominantly. However, the football is not completely full of straight runnings. Quickness, turning skills and changing direction speed namely agility is the crucial for referees to maintain well positioning during match. For this reason, we have modified the classical T-Test for referees by addition side steps, quick turnings and backward steps to test agility skills and their speed. And we compared the T-Test scores with 10 meters and 30 meters sprint tests scores of 74 male referees (Ankara, Turkey) who regularly participating in trainings and regularly refereeing in matches. All referees performed 10 meters and 30 meters sprint tests twice and we recorded the best sprint times. The referees performed the T-Test one time. All three tests have shown normal distribution frequencies. Our results showed a significant corelation between all of three tests; 10 meters and 30 meters (r = 0,660; P < 0,01), 10 meters and T-Test (r = 0,226; P < 0,01), 30 meters and T-Test (r = 0,269; P < 0,01). These results showed that, T-Test scores will be usable to determine 10 meters and 30 meters sprint level of the referees and additionally, T-Test could also give information about levels of other crutial skills for referees as agility. In conclusion, our data showed that the modified T-Test for referees could be used for testing each of the running speed and agility skills of the soccer referees.
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The Paired Assignment Problem

The Paired Assignment Problem

We are given a bipartite graph  = (     , ) where each edge e ∈  has one endpoint in  and the other endpoint in  . Elements of  are normally referred as agents (or people), and elements of  are referred as tasks (or jobs). Then a → ∈ t  means that agent a can perform task t (not every agent can perform every task). In classic maximum bipartite matching problem the goal is to find a matching in  (a set of pairwise non-adjacent edges) that contains the largest possible number of edges. A matching is a one-to-one assignment: each agent can be assigned to at most one task, and each task can be assigned to at most one agent.
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Comparing the Tuberculin Skin Test and T-SPOT.TB Blood Test in Children

Comparing the Tuberculin Skin Test and T-SPOT.TB Blood Test in Children

gen response in the positive control subjects (n ⫽ 7) and a high back- ground in the negative control well (n ⫽ 3). Seven children received posi- tive TST results; 1 child with clinically diagnosed tuberculosis disease had failed the T-SPOT.TB assay and had a negative TST result. Patients with failed assays were younger than the remainder of the study population (4.7 vs 8.7 years; P ⫽ .02). Seven chil- dren received borderline (5–7 spots) T-SPOT.TB results; all received positive TST results, and 5 of 7 children were vaccinated with BCG. There were no differences in age, immunocompe- tence, or disease status between chil- dren who received borderline results and the rest of the study population. The manufacturer recommendation is to repeat the T-SPOT.TB for children who received borderline results, but internationally, 6 to 7 spots often are considered a positive result. When the latter cutoff ( ⱖ 6 spots) was used, con- cordance between the TST and the T-SPOT.TB was 69.7%.
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A test for checking earthquake aperiodicity estimates from small samples

A test for checking earthquake aperiodicity estimates from small samples

Abstract. In recent years, many new models for earthquake recurrence were proposed. Some are focusing on the cluster- ing properties on a small time scale, while others try to model the long term behavior of large mainshocks. To this last pur- pose, there is a growing interest for models that take into ac- count the aperiodicity aiming to a time-dependent hazard es- timate. It is well known that a limited number of inter-event times (IETs) may lead to biased values of the distribution pa- rameters. To overcome this problem different solutions were proposed. This paper focuses on two of them: Monte Carlo simulation of the process and aperiodicity estimated via a sta- tistical proxy. The topics discussed are: 1) how many IETs are needed for a correct estimate, 2) to which extent a Pois- son distribution is equally able to describe the process, 3) the influence of errors associated to paleoseismological IETs, and 4) the goodness of the success ratio from simulations. A simple test is proposed to discriminate real aperiodicity from apparent aperiodicity coming from undersampling.
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Characterization of the postsynaptic protein neurogranin in paired cerebrospinal fluid and plasma samples from Alzheimer’s disease patients and healthy controls

Characterization of the postsynaptic protein neurogranin in paired cerebrospinal fluid and plasma samples from Alzheimer’s disease patients and healthy controls

To minimize nonspecific binding of other proteins dur- ing the immunoprecipitation, all plasma samples were pretreated twice with 20 μl of Novex Dynabeads Protein G (Life Technologies, Carlsbad, CA, USA) per milliliter of plasma and incubated for 1 hour at RT before the beads were magnetically removed as described previously, with some modifications [20]. HI-MS analysis of Ng pep- tides was performed as described elsewhere [16]. In brief, 4 μg of the monoclonal anti-Ng antibodies Ng2 and Ng3 were separately added to 25 μl of Dynabeads M-280 sheep anti-mouse immunoglobulin G (Life Technologies) and cross-linked as previously described [21]. Beads coated with Ng2 and Ng3 were used for immunoprecipitation of plasma to which n-octyl-β-D-glucopyranoside (10%, end concentration 0.1%; Fluka Chemie, Buchs, Switzerland) had been added. The beads and sample were transferred to a KingFisher magnetic particle processor (polypropylene tubes; Thermo Scientific, Waltham, MA, USA) for automatic wash- ing and elution of the Ng peptides and protein. Eluted Ng was collected and dried in a vacuum centrifuge and redis- solved in 5 μl of 0.1% formic acid (FA) in 20% acetonitrile and subsequently analyzed using an ultrafleXtreme matrix- assisted laser desorption/ionization (MALDI) time-of-flight/ time-of-flight (TOF/TOF) MS (Bruker Daltonics, Bremen, Germany). All solvents used were of high-performance liquid chromatography (HPLC) quality.
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How to analyse the spatiotemporal tumour samples needed to investigate cancer evolution: A case study using paired primary and recurrent glioblastoma

How to analyse the spatiotemporal tumour samples needed to investigate cancer evolution: A case study using paired primary and recurrent glioblastoma

Droop, A orcid.org/0000-0001-7695-7480, Bruns, A orcid.org/0000-0002-6970-4036, Tanner, G et al. (12 more authors) (2018) How to analyse the spatiotemporal tumour samples needed to investigate cancer evolution: A case study using paired primary and recurrent glioblastoma. International Journal of Cancer, 142 (8). pp. 1620-1626. ISSN 0020-7136

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Paired Performance Measures The output and outcome measures below must be paired as shown.

Paired Performance Measures The output and outcome measures below must be paired as shown.

PROJECT TYPE COMMON OUTPUTS COMMON OUTCOMES Water, sewer, or infrastructure construction project Households served Businesses served MGD capacity Linear feet Households i[r]

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On the asymptotic t-test for large nonstationary panel models

On the asymptotic t-test for large nonstationary panel models

to worsen the results, at least in small samples. Although a factor structure in the error term alters only slightly the numbers in Tables 2a and 2b (when compared to those in Tables 1a and1b) for the cases (n; T ) = (25; 100) and (50; 200), including cross- dependence makes the empirical rejection frequencies less close to the nominal level 0:05. This is particularly evident as increases, which is expected since the asymptotics is driven by units with I (1) errors and therefore with I (1) common factors in their error term. A possible explanation is that presence of cross sectional dependence makes the convergence of the (cross-sectional) CLT slower, thereby marring the accuracy of asymptotic approximations. However, as the sample size increases, this discrepancy is mitigated, and for (n; T ) = (100; 400) the …gures are very close, as one could realise comparing Tables 1c and 2c.
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The Paired Peers project report

The Paired Peers project report

Kyle, working-class, UWE Paired Peers is three-year qualitative longitudinal project following a cohort of students drawn from two universities in the same English city, the University o[r]

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Expression of the Epidermal Growth Factor Receptors and Ligands in Paired Samples of Normal Breast Tissue, Primary Breast  Carcinomas and Lymph Node Metastases

Expression of the Epidermal Growth Factor Receptors and Ligands in Paired Samples of Normal Breast Tissue, Primary Breast Carcinomas and Lymph Node Metastases

Purpose: In breast cancer, the EGF receptors host an increasing number of therapeutic targets and the interactive mechanisms of actions of the receptors and their ligands justify investigation of the EGF family as an entity. Experimental design: Paired tissue samples of normal breast tissue and primary breast carcinomas were examined in a prospective study of 163 patients. A third sample was obtained from the paired ipsilateral metastatic lymph node from 58 of these patients. The mRNA expression of four EGF receptors (HER1 - HER4) and 11 activating ligands was quantified with real-time RT-PCR. Results: Expression of HER2, HER3, and HER4 mRNA was upregulated in primary carcinomas compared to normal breast tissue while HER1 was downregulated. The mRNA expression of HER3 and HER4 differed between primary breast carcinomas and lymph node me- tastases whereas there was no difference in the expression of HER1 and HER2. The combination of low HER3 and low HER4 expression in the primary carcinoma was significantly more frequent in lymph node-negative patients as compared to lymph node positive patients. Distinct correlation patterns of the receptors and their corresponding activating ligands appeared in both normal breast tissue and in carcinomas, notably for the HER3 and HER4 receptors and their 3 specific ligands: HB-EGF, NRG2, and NRG4. Conclusion: HER2, HER3, and HER4 showed increased mRNA expression in carcinomas and were positively correlated to each other and to specific activating ligands. Furthermore, low HER3 and HER4 expression in the carcinomas correlated to the absence of lymph node metastases.
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Adaptation of Amoeba Plate Test To Recover Legionella Strains from Clinical Samples

Adaptation of Amoeba Plate Test To Recover Legionella Strains from Clinical Samples

Patients and samples. This study prospectively included all respiratory specimens that were collected in February 2015 to September 2015 by the National Reference Centre for Legionella, as part of routine LD patient management, and were of sufficient volume for axenic culture and amoebic coculture. An LD case was defined as a case with clinical and/or radiological findings consistent with pneumonia and positive urinary antigen results (confirmed LD case) and/or positive Legionella PCR results with a respiratory sample (probable LD case). The use of patient data by the National Reference Centre for Legionella was approved by the ethics committee of the Hospices Civils de Lyon; written informed consent was not required, in accordance with the regulations in place at the time of the study. Culture techniques used in this study. All specimens were processed with three culture techniques, i.e., axenic culture, liquid-based amoebic coculture (LAC), and APT (see Fig. S1 in the supplemental material). Axenic culture was performed upon sample arrival at the laboratory, 5 days a week. The samples were liquified using dithiothreitol (Sputasol; Oxoid, Dardilly, France) if necessary. One hundred microliters of each sample was inoculated onto four plates, i.e., buffered charcoal yeast extract (BCYE) (Oxoid); BCYE supplemented with cefamandole, polymyxin B, and anisomycin (BMPA medium) (two plates; Oxoid); and BCYE supplemented with glycine, vancomycin, polymyxin B, anisomycin, bromothy- mol blue, and bromocresol purple (MWY medium) (Oxoid). The plates were incubated for 10 days at 35°C in an aerobic atmosphere (BCYE and BMPA media) or in a 2.5% CO 2 atmosphere (BMPA and MWY media).
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Test statistics for comparing two proportions with partially overlapping samples

Test statistics for comparing two proportions with partially overlapping samples

A range of values for n 1 , n 2 and n 12 likely to be encountered in practical applications are considered which offers an extension to the work done by Choi and Stablein (1982). Simulations are conducted over the range  from 0.15 to 0.5 both under H 0 and H 1 . The values of  have been restricted to  <= 0.5 due to the proposed statistics being palindromic invariant with respect to  and 1   . Varying  is considered as it is known that  has an impact on paired samples tests. Negative  has been considered so as to provide a comprehensive overview and for theoretical interest, although  < 0 is less likely to occur in practical applications.
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Single-cell TCRseq: paired recovery of entire T-cell alpha and beta chain transcripts in T-cell receptors from single-cell RNAseq

Single-cell TCRseq: paired recovery of entire T-cell alpha and beta chain transcripts in T-cell receptors from single-cell RNAseq

reference human databases for each gene region [15]. Random bases were then inserted at the junction seg- ments of lengths 0 bp, 3 bp, 6 bp, and 9 bp to model the junctional diversity of VDJ recombination that occurs in TCRs. Empirically, we calculated from the Jurkat cell line RNAseq data that approximately 0.3 % of all mapped reads mapped to the reconstructed TCR loci. Therefore, for each simulated alpha and beta chain sequence we then again applied GemSim to the syn- thetic TCR alpha and beta sequences to generate sim- ulated read pairs at the required length and error model and concatenated them with the reference RNAseq simulated data from the hg19 models in a ratio of 3:997. This generates realistic error-containing read-pair data generally reflective of a scRNAseq run at the required read length and depth. In these ran- dom runs, the depths were selected so that on aver- age the TCR alpha and beta chains had average coverage of 10×, 50×, and 100×, generating 120 simu- lated paired read files for each read length and aver- age TCR coverage. We defined that scTCRseq had accurately recovered the alpha or beta chain sequence in question if it fully recovered the junction sequence and sufficient V, J, and C gene to uniquely determine the chain that was simulated. We also ran VIDJIL on the simulated data to check the recovery rate of the junc- tion sections. The results of the simulations (Additional file 3: Table S3) show that given sufficient coverage scTCRseq was able to accurately recover both TCR loci at all read length at greater than or equal to 90 % accuracy for TCR average coverage of 50×. Due to the requirement to have reads spanning the entire junctional segments of the alpha and beta chains, VIDJIL was unable to deter- mine any alpha or beta chain sequence for simulated data with read lengths 25 bp or 50 bp, but could accurately de- termine the junction sequence at rates comparable to scTCRseq for coverage of 50× or greater (without deter- mining the unique correct V genes). However, scTCRseq was able to accurately determine the TCR loci at lower coverage, especially for longer read lengths where at 10× coverage and 100 bp read length it recovered 94 % of alpha chain sequences and 100 % of beta chain sequences versus 48 % for VIDJIL in both cases.
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