A biostatistician is conducting a clinical trial to compare five drugs (labeled A, B, C, D, and E) in terms of their mean systolic blood pressure reduction. We wish to know whether there are differenc

need this done before 11:59  4/1/2020 to receive money

Problem 4: An agricultural researcher is investigating the relationship between fertilizer amount and yield of a corn crop, under two different growing conditions. The levels of fertilizer amount (in pounds) are: 40, 60, 80, and 100. The two growing conditions are "sunny" and "shaded". We want to know whether the effect of fertilizer amount on mean yield is different under the two growing conditions. If so, then which pairs of factor level combinations are NOT significantly different? If not, then which levels of fertilizers are significantly different? [Also, if it is of interest for the researcher to predict the corn yield if 90 pounds of fertilizer were used in shaded conditions, what approach would you take, using these data? Do you make any extra assumption to answer this question?] The data and some SAS code are given on the course website. Write a mini-report describing your data analysis of choice and your conclusions to answer the research questions, and giving your recommendation for the best agricultural practice to get good corn yields.

SAS

/* Problem 4 */ DATA prob4; INPUT fert cond $ yield; cards; 40 sunny 45.7 40 sunny 48.5 40 sunny 43.7 40 sunny 44.9 40 shaded 32.6 40 shaded 35.7 40 shaded 33.1 40 shaded 29.4 60 sunny 55.6 60 sunny 53.8 60 sunny 59.2 60 sunny 55.7 60 shaded 41.6 60 shaded 37.8 60 shaded 40.2 60 shaded 39.4 80 sunny 67.8 80 sunny 66.2 80 sunny 64.9 80 sunny 62.6 80 shaded 54.9 80 shaded 51.4 80 shaded 50.2 80 shaded 55.7 100 sunny 54.7 100 sunny 55.6 100 sunny 56.8 100 sunny 51.2 100 shaded 61.1 100 shaded 59.9 100 shaded 58.3 100 shaded 60.0 ; run;