Calculated t-values

It is evident that the calculated t-value for the constant value, a, is less than the critical t-value. From the statistical viewpoint this value, then, is negligible. The data can then be recalculated according to the first order model without a constant value. Table III shows the result of this recalculation. There are no changes relating to the conclusions made concerning the author determination. 

As an example, a calculated t value of 4 with one degree of freedom (see Equation 6.9) is significant at the 84.4% level of confidence (a = 0.156). Similarly, a calculated F value of 16 with one degree of freedom in the numerator and one degree of freedom in the denominator (see Equation 6.38) is also significant at the 84.4% level of confidence. 

If the calculated t value exceeds the tabulated value for the indicated degrees of freedom, then chances are 95-out-of-100 or 99-out-of-lOO that the two averages are significantly different. 

If the null hypothesis is true, the calculated t-value is smaller or equal to that obtained from Table 9.1 for the respective degree of freedom and a chosen probability P, i.e., there is a significant difference between the both means if Calculated > ti-p(Tabie)-... 

The critical value of the t test can be abbreviated as fa(2),v, where a(2) refers to the two-tailed probability of a and v = n — 1 (degree of freedom). For the two-tailed t test, compare the calculated t value with the critical value from the t distribution table. In general, if t > ta(2),v, then reject the null hypothesis. When comparing the means of replicate determinations, it is desirable that the number of replicates be the same in each case. 

Numerous scientist have calculated t-values as a function of p/p,).24,25,26,27 A general accepted formulation is the Halsey equation 28... 

Test of the Empirical Equation - Table I compares the calculated T values at 1000 Hz using the DSC data at a heating rate of 10 C per min. T was calculated using both the assumed activation energy of 400 kJ/mole as well as the experimentally determined values by RSA II multiplex experiments. The predicted data were compared with the extrapolated peak loss factor temperature from the nomographs of RSA II and beam data. 

Table 41.2 Critical values of Student s t statistic (for two-tailed tests). Reject the null hypothesis at probability P if your calculated t value exceeds the value shown for the appropriate degrees of freedom = (ni — 1) + (02 1)...

Solution The standard deviations are clearly strong functions of frequency. Thus, the appropriate Student s i-test is that for paired variates, equation (3.38). The calculated t-value is texp = 1-710. An interpolated table eft-test values is presented as Table 3.6. The significance level at a degree of freedom v = n — 1 = 73 corresponding to texp = 1-710 is p = 0-0915. The value oft corresponding to the cc = 0.05 level is fo.o5 = 1-993. As texp < fo.05/ the 0.05 significance level, the two means are not significantly different. 

The ealeulated t-value was compared with the theoretical t-value (t-Table) for the confidence interval of 95% and it was found that the calculated t-value for Al, Ni, V Ti (Table. 1) is lesser than the theoretical t-value.-Therefore, it was concluded that except for Fe, there is no significant difference between ICP XRF results for these elements at 95% confidence level (2a). However, for Fe, there is no significant difference at 98 % (3a) confidence level. 

We used Primer Express software (ABl) in calculating the T of primers and probes. Any program should work, just make sure to use the same program and conditions for calculating T , values of both the primers and probes. 

The null hypothesis is accepted if the two means x- and X2 differ only randomly at risk level a, that is, if the calculated t value is lower than the tabulated value for t l - a/2 f= + 2 2). 

Od V "1 + 2 The critical t-value is (according to Table 2.6) t(l - a/2 i-b 2 2) = t(l-0.05/2 12) = 2.18. This means that the calculated t-value is greater than the critical value, that is, the two-sided test is significant. The differences in the titanium determination in the two laboratories cannot be explained by random errors. 

This implies the need for calculated t values of 20 or even 40 to meet our common expectation of a 10 or 5%, respectively, error of estimation ... 

Because the magnitude of the calculated t value (-3.33) is greater than the tabled value (2.201) with a = 0.05 and df = 11, the two means are considered to be statistically different. 

The calculated T, value for Pro comes from poly(GVGVP) when the experimental values of Val and Gly are used. This hydrophobicity value of —8°C is unique to the /1-spiral structure where there is hydrophobic contact between the Val 7CH3 and the adjacent Prof 5CH2 and the intertum Prof+3 /KIH2 moieties. 

When t values are determined in a laboratory, the rubber septum will usually be contained in some type of glass container. Condensation and re-evaporation from the inside surfaces of the glass container can affect evaporation rates and calculated t values (13). The relevant factors can be represented as follows. 

In view of the fact that the rotation of the micelle also contributes to the depolarization of the fluorescence of the probe, microviscosity should be calculated by using Xl rather than Dutt ° calculated t) , values of SDS, CTABr, 2-PDS, 3-PDS, 4-PDS, and 6-PDS micelles by using the calculated values of Xl, which show that both probes sense almost identical microviscosity for a given micelle. Both probes, DMDPP and C6, are concluded to reside in the Stem layer of all six micelles. 

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