The process of measurement, which is the assigning of values or scores to phenomenon (objects or events) according to rules is very important to research.
One of the aims of the research is to obtain a better understanding of the relationships among variables.
Researchers depend on observed characteristics of a sample to approximate characteristics of a population. Therefore, for the approximation to be as accurate as possible, the measuring instruments must be very dependable.
Research instrument represents a variety of data collection devices. These devices should be able to measure abstract and complicated qualities such as personality, interest, intelligence and so on.
Research instruments are in three basic forms of;
- Researchable instruments,
2. Standardized instruments,
3. Instruments adapted from previously accepted published research works.
The reliability coefficient or index for standardized instruments could be used. But they are only when there are similarities between circumstances and environmental locations of former and present research efforts.
It’s important to note that a research instrument should be constructed to guarantee;
- The optimization of responses from members of the sample size and,
2. The minimization of measurement or response errors.
The construction of a measurement instrument should be preceded by a total break down of the problem area into testable hypotheses or research questions.
Having the problem area in testable hypotheses lays the foundation for constructing a research instrument that performs the following functions.
Functions of Research Instruments;
- Collecting reliable research data:
The reliability of a research outcome depends on the dependability of data.
The dependability of a research data depends on the validity and reliability of the nesearch instrument (the data gathering tool) used
2. Establishment of previous behaviors:
Research instruments are used to gather information about current and previous behaviors. Previous behaviors set standards for identifying and measuring deviations and abnormalities.
Valid and reliable research instruments are used to guarantee appropriateness, accuracy and relevance of research data. Statistics analyze data but don’t have the capacity to sort out wrong or false data.
Research instruments are used to acquire factual information about a population.
For instance, a measuring instrument like interview could be used to find out causes of broken homes.
Research instruments are tools for setting standards in an institution or community