Page 270 - Area 9 - Relevant Document

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Experimental Design

Experiment - a guided procedure of obtaining the solution.
Experimental Design - a set of rules that governs the conduct of an
experiment. It includes the plan and actual procedure of laying out an
experiment.

Statistics - concerned with the scientific methods of collecting, organizing,
summarizing, presenting and analyzing data, as well as drawing valid
conclusions and making reasonable decisions on the basis of such analysis

Basic Principles:

1. Treatment - a procedure, the effect of which is to be measured and
compared to the effect of other treatments.
Example: fertilizer trials ---- kg P/ha

2. Experimental unit - a unit material to which treatments are applied.
Example: Insecticide concentration in ppm treated to a leaf. The
leaf is the experimental unit/material.

3. Experimental error- measure of the variation among experimental units
treated alike.
Sources:

A. Inherent variability, which exist in the experimental unit. Ex.
Seeds; size and shape.
B. Lack of uniformity in the physical; conduct of the experiment.
4. Replication - the number of times the treatment is applied to the
experimental unit. Its purpose is to minimize the experimental error.
5. Randomization- the manner in which the treatment are allocated to the
experimental unit. Its purpose is to have a valid measure of the
experimental error.
6. Local control- to implement or consider this, the treatments are
arranged so that known causes of variations are eliminated.

Steps in planning and conducting experiments

1. Formulation of the statement of the problem and experimental
objectives.
2. Formulation of the hypothesis to be tested.
3. Logical evaluation of the problem.
4. Selection of the procedures for research.
4.1. Selection of treatments to be tested.
4.2. Determination of the population of inference.
4.3. Selection of the characters to be measured.
4.4. Determination of the required precision and the selection
of the experimental design