The article “Nutrient Deprivation Improves Field Performance of Woody Seedlings in a Degraded Semi-arid Shrub-land” (R. Trubata, J. Cortina, and A. Vilagrosaa, Ecological Engineering. 2011:1164–1173) presents a study that investigated the effect of varying the; type of fertilizer on the height of certain Mediterranean woody tree species. In one experiment, three samples, each consisting of ten trees, were grown with three different fertilizers. One, the control group, was grown with a standard fertilizer. Another was grown with a fertilizer containing only half the nutrients of the standard fertilizer. The third was grown with the standard fertilizer to which a commercial slow-release fertilizer had been added. Following are the heights of the trees after one year. These data are consistent with the means and standard deviations reported in the article.
- a. Construct an ANOVA table. You may give a
range for the P-value. - b. Can you conclude that the heights differ among the types of fertilizer?
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