Student s t-test

Table 1.10. Various Forms of the Student s t-test. For Details and Examples see Text. The Expression Vj = Vj ... 

FIGURE 1. Effect of acute METH on serotonergic parameters Significantly different from control, p<0.05 by Student s t-test. 

Statistical analysis. Values are given as the mean SEM. Data are represented as averages of independent experiments, performed in duplicate or triplicate. Statistical analyses were done using the Student s t-test. P < 0.05 was considered statistically significant. 

This set of articles presents the computational details and actual values for each of the statistical methods shown for collaborative tests. These methods include the use of precision and estimated accuracy comparisons, ANOVA tests, Student s t-testing, The Rank Test for Method Comparison, and the Efficient Comparison of Methods tests. From using these statistical tests the following conclusions can be derived ... 

Student s t-Test for the Difference in the biases between Two Methods ... 

The cultures were obtained and maintained in the same conditions described above and observed with the same procedure at the same time intervals. The different morphogenetic effects induced by active fractions are evaluated by the following parameters (i) number of cells in the main filament, (ii) kind of filaments (caulonema, chloronema, rhizonema) (Figure 2), (iii) order of secondary branches, (iv) number of cells without ramification from the apex, (v) number of cells in the I and II order filaments (Table 1). Significance of differences is evaluated by Anova or Student s t test as appropriate. 

In this case study, 11 different extraction methods (Table 1) were applied to a 1000 m line of 15 B/C-horizon soil samples (<0.25 mm) across the Talbot VMS Cu-Zn deposit in northern Manitoba, Canada (Fig. 1), followed by ICP-MS analysis. Student s t test and minimum t probability statistics provide a tool to rank the exploration performance of each method (Stanley 2003 Stanley Noble 2008). By... 

Student s t test statistics and t probability were calculated to quantify the contrast between anomalous and background populations in each extraction method data set (Student 1908 Stanley Noble 2008). Sample sites were designated anomalous based on the projection of mineralization and a fault zone in the cover rocks. For most methods, Zn... 

Because of the way r is defined, its value always lies between 0 and 1. Values close to 1 indicate a strong relationship, whereas values near zero imply little relationship. It is possible to use a version of the Student s t-test (Miller and Miller 1993) to see if the observed correlation is significant at a particular level of confidence (usually 95%), or to conclude that such a correlation may have occurred by chance. The equation for this is ... 

Two-sample Student s t test, Wilcoxian-Mann-Whitney Rank Test, and so on. 

The analysis of rank data, what is generally called nonparametric statistical analysis, is an exact parallel of the more traditional (and familiar) parametric methods. There are methods for the single comparison case (just as Student s t-test is used) and for the multiple comparison case (just as analysis of variance is used) with appropriate post hoc tests for exact identification of the significance with a set of groups. Four tests are presented for evaluating statistical significance in rank data the Wilcoxon Rank Sum Test, distribution-free multiple comparisons, Mann-Whitney U Test, and the Kruskall-Wallis nonparametric analysis of variance. For each of these tests, tables of distribution values for the evaluations of results can be found in any of a number of reference volumes (Gad, 1998). 

Significantly different from controls (P < 0.05, Student s T test)... 

Lactic acid fermentation was the topic of a paper by Vaccari et al.35 In this work, lactic acid, glucose, and biomass were determined over the course of the reaction. The measurements were made in real time, using a bypass pump and flow-through cell for the NIR measurements. Instead of using normal chemomet-ric statistics, the authors used correlation coefficients, mean of differences, standard deviation, student s t-test, and the student test parameter of significant difference to evaluate the results. Under these restrictions, the results appeared fairly good, with the biomass having the best set of statistics. 

The samples were injected intravenously to Balb/c mice on days 14, 17, and 20. < 0.01 vs. CDDP by student s t test. 

When the statistieally sophisticated psychologists realized what I was doing, they had a field day pointing out my failings unjustified assumptions, violations of statistical theory and other mathematical crimes. They talked about ordinal scales versus ratio scales and scolded me for not using analysis of variance instead of Chi-square and Student s T tests of significance. 

Statistics. The levels of significance between two sets of unpaired results were determined according to Student s t test. 

Effect of matrix degradation on the rate of demineralization of incipient erosive lesions in root dentin. Specimens were subjected to daily alternating incubations with HAc pH 5.0 (V,Y) or pH 5.5 ( , ) and either collagenase (TM) or buffer (V,ni (n=5). Values represent mean SD. Levels of significance were calculated according to Student s t test. P<0,05, P<0,01 vs. buffer-treatment. 

The Student s t-test probability (TP) measures the geochemical contrast (essentially equivalent to precision) of an exploration method. This probability identifies the likelihood that anomalous and background concentrations, defined by a specific threshold, are derived from the same population by measuring the difference between the mean anomalous and background concentrations. The lower the TP e.g. the minimum TP for any threshold MTP), the more geochemical contrast and the more likely that random variations will not influence or change the results. 

Mean + S.E. of the mean, calculated on the total number of mice per group (a non-tumor-beaiing mouse was counted as zero but incorporated into the calculation). The differences in median size of treated and control series were statistically significant (Student s t-test) at P < 0.05 unless for where P < 0.10 only. 

Values represent Mean ( S.E.M.) of 3-4 replicate (by direct solid phase RIA) and have been corrected for binding to baseline control antigen BSA. Values not significantly >0 by Student s T-test (P<0.05) reported as 0. No significant binding was detected using prebleed sera preparations obtained from the mice prior to Immunization. Representative data shown. 

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