Sample size reporting calculation

Sample size is 100 ml and distillation conditions are specified according to the type of sample. Temperature and volume of condensate are taken simultaneously and the test results are calculated and reported as boiling temperature as a function of the volume recovered as shown in Table 2.1. 

A comparison is made of the detector signal in the absorption versus scattering mode. Particle sizes are calculated for the standard latex samples and their mixtures using recently reported analytical. methods which account for imperfect resolution. 

Calculate the percentage of each particle size range retained in the sand sample. Also report the cumulative percentages. 

Qiu W, Lee MLT, Whitmore GA (2008) Sample size and power calculation in microarray studies using the sizepower package. Technical report, Bioconductor... 

A detailed statement of the basis of the sample size calculation should be included in the protocol and in the final report. This statement should contain the following ... 

The CONSORT statement (Moher et al. (2001)) sets down standards for the reporting of clinical trials and their recommendations in relation to the sample size calculation are in line with these points. 

A revised sample size may then be calculated using suitably modified assumptions, and should be justified and documented in a protocol amendment and in the clinical study report... The potential need for re-estimation of the sample size should be envisaged in the protocol whenever possible. ... 

A meta-analysis for continuous data cannot be calculated unless the pertinent standard deviations are known. Unfortunately, clinical reports often give the sample size and mean ratings for the various groups but do not report the standard deviations (or standard error of the mean), which are necessary for effect size calculations. Thus, investigators should always report the indices of variability (e.g., confidence intervals, SDs) for the critical variables related to their primary hypothesis. 

The statistical analysis approach is to calculate 95% confidence intervals for the proportion of participants in each group (placebo and combined active) reporting a headache. This analysis approach is reasonable because the sample size is sufficiently large (that is, the values, pn, in each group are at least five). Satisfying this assumption enables us to use the Z distribution for the reliability factor. 

As a final result the producer issues a material certified for a number of parameters, based on the minimum sample size determined in the homogeneity study. This information must be given to the end user in the form of a certificate. The certificate or the accompanying report must also state the uncertainty and the way it is calculated. 

Unfortunately, many researchers still report only the mean and range limits and do not cite the SD or even the sample size (number of specimens, n). Such information is of very limited value, since the range is only a crude and inefficient measure of variation and its expectation depends on n. With the mean, SD, and n, one can calculate statistical ranges, the probability of any particular deviation, and carry out many other powerful statistical assessments. 

In Figure 3 are demonstrated the nitrogen adsorption/desorption isotherms of the obtained mesophases together with their pore size distribution calculated by the BJH method [7], The specific surface area (Sbei), the external specific surface area Sexd, the total specific pore volume (Ffot) and the specific micropore volume (F icro) [8] are reported in Table 2. The isotherms can be classified as type IV, which are typical for mesoporous solids [14]. However, with the increase of ZSM-5 crystallinity they change fi om a typical type IV (sample A and D) to an intermediate between type IV and type I isotherm (sample B and C), the latter indicative for the presence of micropores [14]. 

Table 3 reports characterization results of the samples obtained by Route A along with those of the commercial powders. The percentages of anatase and rutile in the samples were estimated through the Spurr and Myers method [11]. The ciystallite sizes were calculated from the Scherrer equation [12]. 

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