2. Magnesium Ammonium Phosphate and Chrysanthemums. Walpole et al. (2007) provide data from a study on the effect of magnesium ammonium phosphate on the height of chrysanthemums, which was conducted at George Mason University in order to determine a possible optimum level of fertilization, based on the enhanced vertical growth response of the chrysanthemums

(a) Do different concentrations of MgNH4PO4 affect the average attained height of chrysanthemums? Look at the 95% credible sets for the differences between treatment effects.

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