Trimming data

Robust Statistics use trimmed data for the calculation of the estimated values. That means, that a part of the data set in the tails is excluded or modified prior to or during the calculation. An easy example is the use of the interquartile range (the range between the first and the third quartile) instead of the whole data set. 

Trimmed data a certain part of the data on both tails of the data set is excluded prior to the calculation of the mean... 

The amplifier (5) boosts the signal, eliminates temperature coefficients, and adjusts the offset. The low pass filter (6) limits the bandwidth. The drive circuit is a closed loop system to achieve a stable drive oscillation. It consists of a structure (not drawn) that detects the oscillation movement of the drive of the yaw-rate sensor element, a control unit (2), and an actuator (not drawn). The start circuit (9) initiates the drive oscillation at power on. The block (8) generates all necessary adjustment signals and includes the logic circuit for the trim and an EPROM (erasable programmable read-only memory) for the storage of the trim data. 

Data reduction involves the mathematical procedures applied to the results returned by the participants. Usually, there is a procedure to identify outliers - results that are remote from the anticipated value, probably caused by a transcription error or analysis of a different sample. As inclusion of these results could distort subsequent calculations it is useful to apply a statistical routine (e.g., greater than 3SDs from the mean) to eliminate these data. The trimmed data are then taken through the chosen calculations that, with few exceptions, are determination of the number and range of results, the mean, SD, and CV. If it is suspected or has been definitely shown that the distribution of data is not normal, the median should be found. In schemes where there are hundreds of participants, subroutines are included to re-examine results and present these calculations for a specific method or other variable. 

Combustion controls such as oxygen trim help to maintain optimum operating conditions, especially on gaseous fuels. Instrumentation can give continuous visual and recorded information of selected boiler and plant functions. To be effective, it must be maintained and the data assessed and any required action taken before the information is stored. 

Fig. 8. Calculated values of (top) /(0), (center) /(75), and (bottom) J (653) for acid-unfolded apoMb, pH 2.3, 25°C. The horizontal lines show the mean values of J (75) (0.19 ns rad-1) and /(653) (0.020 ns rad-1), and the 10% trimmed mean value of J (0) (0.97 ns rad-1). The average buried surface area, calculated using the values of Rose and co-workers (Rose et al., 1985) and averaged over a seven-residue window, is also shown in the center figure (solid line, no data points, right-hand scale). Black bars indicate the positions of the helices in the folded structure of myoglobin.

Statistical Analysis. Analysis of variance (ANOVA) of toxicity data was conducted using SAS/STAT software (version 8.2 SAS Institute, Cary, NC). All toxicity data were transformed (square root, log, or rank) before ANOVA. Comparisons among multiple treatment means were made by Fisher s LSD procedure, and differences between individual treatments and controls were determined by one-tailed Dunnett s or Wilcoxon tests. Statements of statistical significance refer to a probability of type 1 error of 5% or less (p s 0.05). Median lethal concentrations (LCjq) were determined by the Trimmed Spearman-Karber method using TOXSTAT software (version 3.5 Lincoln Software Associates, Bisbee, AZ). 

The mortality data were eompared for field and eultured heart urchins using two way ANO-VA. Survival data were statistically analyzed in ToxCalc using the Trimmed Spearman-Karber point estimate test to determine the lethal concentration LC i,. 

All of the foregoing calculations are simply to trim the data set by removing outliers in accordance with the set criteria. All that remains is to calculate the mean value for the sample, the repeatability and reproducibility of the trialled method and the HORRAT ratio. These values can be calculated using a one way ANOVA method similar to that described in Table 29 and given in Table 33 and the final values in Table 34. 

FIGURE 3. Graphic displays of the cis and trims conformations of 9-benzyladenine (a) and variation of the potential energy of the azaheterocycle as a function of the torsion angles Z and r2 (b). Contours are shown at intervals of 1 kcalmol-1 with the lowest energy level (—17.6 kcal mol 1) indicated by the symbol (x). (Data taken from Ref. 148, with permission)... 

Trim the data by eliminating test results from noncritical processing steps and delete all gratuitous numerical information. 

FASTX-Toolkit http //hannonlab.cshl.edu/ f astx to o 1 k i t/i ndex.html Sequencing data quality assessment and preprocessing, for example, adapter sequence removal, sequence trimming, and conversion of sequence reads to reverse complement... 

Raw data for all bioassays, except algal test, were analyzed using the Toxcalc Toxicity Data Analysis and Database Software, vers. 5.0 (Tidepool Scientific Software). Point estimations were calculated by concentration/response regression using Probit Analysis as first choice and Trimmed Spearman-Karber as second, if Probit was not possible. If the raw data did not allow the respective L(E)C50 to be calculated at the highest tested concentrations, then these values... 

Rohsenow. W. M. A Method of Correlating Heat Transfer Data for Surface Boiling Liquids. Trims. ASME. vol. 74. p. 969, 1952. 

There are other minor nonequivalencies of ISO test procedures compared to ASTM standards, but for color difference the ISO Test Procedure No. 105 is unique. Those who use Colour Measurement Committee (CMC) procedures—particularly CMC 2 1 Lightness to Color ratio—claim that it facilitates a uniform description for acceptability decisions that is better than any other system in existence. These equations permit the use of a single number tolerance, DEcmc, in a nearly uniform color space. The CMC formula is a modification to the perceptibility CIELAB formula. It is fully described elsewhere in this book, but it deserves some brief notice here because, after all, it is an ISO procedure. The CMC developed the basic British Standard No. 6923, Calculation of Small Color Differences. Soon afterward, in 1989, the American Association of Textile Chemists and Colorists (AATCC) adopted AATCC Test Method 173, CMC Calculation of Small Color Differences for Acceptability. Ford Motor Company indicated a preference for using CMC 2 1 ratio color difference for plastics weathering data for plastics interior trim materials. 

There has been some interest in the chemistry of aminonitroazoles when used as high energetic compounds. Data concerning direct introduction of the amino group into the nitroazole cycle have been absent in the literature till the present time. We have studied the vicarious nucleophilic substitution of l-methyl-4-nitropyrazole and also l-mcthyl-4-nitroimidazole (Table 3.10), 4-nitro-2-phenyl-1,2,3-triazole (Table 3.24), and nitrobenzimidazoles (Table 3.25) under the effect of 1,1,1-trim-ethylhydrazinium halides and 4-amino-1,2,4-triazole by NMR spectroscopy (DMSO-<76) (Scheme 3.5) [220, 272-278] ... 

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