Finals Flashcards
The treatments are assigned completely at random so that each experimental unit has the same chance of receiving any one treatment.
Completely Randomized Design
It is considered a ___________ ______ if there is a difference among experimental units receiving the same treatment.
Experimental error
the CRD is only appropriate for
experiments with __________ _______ ____, such as laboratory experiments, where
environmental effects are relatively easy to control.
homogenous experimental units
T/F. field experiments, where there is generally large variation among experimental plots, in such environmental factors as soil, the CRD is oftenly used.
False, CRD is RARELY used
the simplest type of design to use.
Completely randomized design
What is the most important requirement for the use of the CRD design?
homogeneity of experimental units.
What are the methods of Increasing Accuracy of Experiments in CRD
- Increase the size of the experiment by increasing the number of replicates.
- Refine the experimental technique.
- Handle experimental material so that the effects of variability are reduced.
T/F. In CRD, data should be collected by the same person using the same units.
True
What is the Step 1 in CRD?
Determine the total number of experimental plots (n) as the product of
number of treatments (t) and the number of replications (r);
What is the Step 2 in CRD?
Assign a plot number to each experimental plot in any convenient manner;
What is the Step 3 in CRD?
Randomly assign the treatments to the
experimental plots
These are factors beyond control (extraneous factors)
Experimental error
Test hypotheses for statistical significance of comparisons of treatment means, where “treatment” or “factor” is the characteristic that distinguishes the populations.
ANOVA
The one-way ANOVA is useful when we want to compare the effect of _______ _____ __ ___ ______and we have multiple observations at each level.
multiple levels of one factor
T/F. The treatment difference is said to be real if the treatment variation is sufficiently smaller than the experimental error.
False. The treatment variation should be larger than the experimental error.
a ___________ _ ____ in the analysis of variance indicates the failure of the experiment to detect any difference among treatments.
nonsignificant F test
What does the CV indicate?
degree of precision
T/F. The higher the cv value, the lower is the reliability of the experiment.
True
Example studies for CRD-unequal replications.
- Animal feeding experiments where the number of animals for each breed is not the same.
- Experiments for comparing body length of different species of insect caught in an insect trap.
T/F. As a general guideline, the F value should be computed only when the error d.f. is six and below.
False, six or more.