ANOVA is a technique that permits the comparison of the equality of means for multiple populations. Thus, 3 means could be compa
red and a determination of whether or not one of the means is significantly different from others can be made. This technique is extremely useful, but, as is always the case, the application requires a firm understanding of models assumptions. Consider the following scenario. A meticulously determined random sample of 200 observations is taken from a very large population. This data divides into 4 groups or factor levels, and a numerical measure for each observation is recorded. The population distribution of the measure appears to be slightly skewed positive. The 4 groups have the following number of observations 30, 100, 15 and 55. Which of the following statements leads to the greatest concern in using ANOVA as an analytical technique. a. Unequal sample sizes among groups can seriously affect the power of the test.
b. Slightly skewed positive distribution of population measures seriously affect the power of the test.
c. In this scenario, I should be concerned about whether the data has been gathered in a biased fashion.
d. Four is not a sufficient number of groups into which to divide the data.
c. In this scenario, I should be concerned about whether the data has been gathered in a biased fashion.
Explanation:
ANOVA is a statistical method which separates observed variance data into different components to use. One way ANOVA is used for three or more groups of data. The greatest concern in ANOVA is that the data gathered should not be biased.
Anaerobic respiration is the production of Energy(ATP) in the absence of oxygen. Some dissimilatory metals reducing microorganisms reduces metals in the absence of oxygen during anaerobic respiration. These microorganisms use metals as terminal electron acceptor rather than molecular oxygen. These microbes use it to conserve energy by oxidizing organic materials and reducing metals.
