AGRO 3503, Unit I-4 Quiz (20 pts).
NOTE: Print this out first in order to find solutions to the questions from the notes and link given below in Part II.
Part I. General statistics. (15 pts)
1. A good field study should always include a:
A. soil pH test B. control treatment
C. at least one unknown treatment D. independent consultant
2. In a field study of the effect of corn seed treatments on yield, the independent
variable is:
A. the corn B. the seed
C. the seed treatments D. yield
3. A factorial designed, RCB study of the effects of 3 N fertilizers applied at
3 rates each and at 3 different timings has how many total treatments per rep?
A. 3 B. 6 C. 9 D. 27
4. The overall measure of variability of a study can be inferred by the:
A. coefficient of variation B. correlation coefficient
C. mean D. median
5. Several different treatments were applied to a grain sorghum study to test their effects
on yield. In a well-designed study with plenty of replications, several locations and
fours years of data, no significant effects were found among any of the treatments
when analyzed using all appropriate statistical tools. It can therefore be concluded
that:
A. the study was flawed
B. there was too much human error involved
C. something in the environment was inhibiting the treatments
D. the hypothesis was not proven
6. If a company says their product increases rice yields by 30 bu/acre based on the
testimony of 10 farmers who have tried the product, what is your response? (2 pts)
7. You are assigned to study the effects of four herbicides on control of barnyardgrass
in rice. All herbicides will be applied pre-emergence at the same time.
1) how will you design this study?
2) what is the hypothesis?
3) What is the independent variable(s) that you will measure to analyze
statistically?
Part II. For solutions to these questions, refer to the link below of the Arkansas wheat
variety evaluation studies.
1. Wheat variety tests are conducted at multiple sites across the state:
A. in case there is a crop failure somewhere
B. to examine performance under a broad range of growing conditions
C. to increase the standard deviation and reduce the C.V.
D. due to licensing agreements with seed companies
2. At each location, how many replications per variety were there?
A. 3 B. 4 C. 5 D. 6
3. Wheat yields were expressed as bu/acre at what % moisture?
A. 10.5 B. 12.5 C. 13.0 D. 15.0
4. In the 2001-2002 results at the Rohwer, AR location, the difference between the
STANDARD and the HIGH input tests were that the:
A. HIGH was irrigated, STANDARD was not
B. HIGH received 60 lbs N/acre more fertilizer
C. HIGH was treated with herbicides, STANDARD was not
D. HIGH was treated with ‘Tilt’ fungicide, STANDARD was not
5. In the 2001-2002 results at the Rohwer, AR location, which of the following
varieties yielded significantly LESS than 70 bu/acre?
A. Dixie 011
B. Roane
C. Terral LA411
D. Pioneer 1551