Question

An agricultural researcher wishes to compare the yield of four different varieties of wheat. 64 plots of land are available for an experiment. On each plot of land one of the varieties of wheat will be grown. At the end of the experiment the yield for the different varieties will be compared. 32 of the plots are at one site (site A) and the other 32 plots are at another site (site B). The soil at site A differs significantly from the soil at site B. The researcher wishes to design an experiment. In this example, why might a randomized block design, with blocking by soil type, be preferable to a completely randomized design?

Answer 1

A randomized block design, with blocking by soil type, would be preferable in this experiment to account for the significant difference in soil conditions at the two sites and ensure an accurate comparison of the yield of different wheat varieties.

Step-by-step explanation:

A randomized block design, with blocking by soil type, would be preferable to a completely randomized design in this experiment because the soil at site A differs significantly from the soil at site B.

By using a randomized block design, the researcher can ensure that each variety of wheat is planted in equal proportions in both sites A and B. This design allows for a more accurate comparison of the yield of the different varieties, while accounting for the variability in soil conditions.

Here's how the researcher can implement a randomized block design:

1. Divide the 64 plots of land into two blocks of 32 plots each: one block for site A and another block for site B.
2. Randomly assign the four varieties of wheat to each plot within each block.
3. Record the yield for each plot at the end of the experiment.
4. Analyze the data using appropriate statistical tests to compare the yield of the different wheat varieties while considering the blocking factors.