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Rationale / value of using statistics statistics is a powerful tool to objectively compare experimental data uncover relationships among variables experience an aspect of the practice of science like real scientists prepares you for a statistics course, a common math class taken in college

1Characterization of experimental data

is the SD in the distribution of means; used in statistical tests.

standard error of the mean (SEM) = is a measure of the variation in the data.

sample standard deviation (SD) = is the average value in the above graph.

sample mean =

2Elimination of outliers: Q-testQ =

N (sample size)Qc345678910

0.940.760.640.560.510.470.440.41For example: is the value of 25 an outlier in the followingdata set ?10, 11, 13, 14, 25In this example,Q =

thus, the value of 25 is an outlier and may be deleted insubsequent data analysis. The Q-test should be used todeleted only a single data.Table 1. Qc values.Outlier data that significantly differs from others its deletion would reduce variability in the data its deletion may make it easier to detect differences between experimental conditions delete if Q > Qc

3Chart11217100.00039599251711210.00088322562229140.00203099011410170.00478350411217100.01140030381915200.02693814720.06114444880.12744204830.23035702570.33968781710.38910.33968781710.23035702570.12744204830.06114444880.02693814720.01140030380.00478350410.00203099010.00088322560.0003959925

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