Meaning, Need and Importance of Statistics in Educational Assessment
Statistics - (Related with data) - The word statistics originated from latin word 'status' or from italian word 'statistal'. Both these words mean 'political state'. Earlier the term was assigned to the accounts of the states. But today it is used in the subjects like science, education, psychology, economics, sociology etc.
According to -
Vodington - Statistics is the science of estimates and probabilities.
Tate - You compute statistics from statistics by statistics..
Kendall - Statistics is the science of collecting, analysing and interpreting numerical data.
Usually the word statistics carries the following three common meanings-
In the first place, it refers to numerical facts. e.g.- Statistics (numerical facts) concerning the Birth and Death, School attendance, Output of Industrial plants and agriculture fields etc.
As a second meaning, it refers to the methods of dealing with numerical facts. Here statistics is taken as science of collecting, classifying, summarizing, analysing and interpreting the numerical facts.
In its third meaning, statistics refers to the summarized figures of numerical facts such as percentages, averages, means, medians, modes, standard deviation etc. Each of these figures separately is referred to as statistics.
Tete has beautifully summarized these different meanings of the world statistics in the following witty comments - "It's all perfectly clear; you compute statistics (mean, median, mode etc.) from statistics (numerical facts) by statistics (statistics as a science or methodology)."
The following terms are used in statistics in the study of above mentioned definitions -
Collection - Gathering data by various methods.
Classification - Classification of data into different categories. There can be different bases of classification.
Presentation - Presentation of data with the help of tables, pictures or diagrams.
Analysis - Various types of results are sought by using different statistical methods.
Interpretation - Some conclusion is obtained from the sought results.
Need and Importance of Statistics in Educational Assessment
The need and the importance of statistics in different subjects and in general are as following -
1. Construction and Standardization of tests
Statistical methods help in construction and standardization of various test and measures like Achievement tests, Intelligence tests, Aptitude tests, Attitude scales etc.
2. Interpretation of the results of tests
Scores obtained in tests are always relative and not absolute. Hence they are meaningless in themselves. Statistical methods help in their proper presentation, comparison and interpretation. Here statistics helps us in the following ways -
To know individual differences of our students
To render guidance to the students
To compare suitability of one method over the other
To compare results of one system of evaluation with the other
To compare one institution with the other
To make selection, classification and promotion of students
To keep various types of records and furnish Educational Statistics etc.
3. Simplification
We can present comprehensive data in a simplified form. It will save us time and labour and will also give us the correct results.
4. Comparative Studies
It helps us in the comparative studies of different groups or different individuals. e.g.- comparison of two institutes.
5. Knowledge of Validity
It validates that a test measures the aspects for which it has been constructed.
6. Knowledge of Reliability
It ensures us that in order to measure a particular aspect we can rely on the given test.
7. Useful in Research Work
Statistics proves useful in the research work in the context of effects of teaching methods, utility of curriculum and achievement of educational objectives.
8. To know Correlation
We can find the correlation between two or more variables along with the quantity of correlation.
9. Selection of a Sample
Most of the studies are conducted on sample in the fields of Education and Psychology. But for sample, it is essential that the same should be the representative of the universe. In selecting representative sample, statistics contributes significantly.
Functions of Statistics
Represents data in numerical form.
Represents data in comparative form.
It creates correlation between two types of data.
It verifies theories of science.
By using statistical methods, we can foretell about human behaviour.
By using statistical results, we develop personal knowledge and experience.
With the help of statistics, we can give scientific form to data.
It shows difficult programs in easy way.
Thus it can be easily concluded that statistics is very helpful to the teachers in the proper functioning of their various duties. It gives a definite direction to the process of teaching and learning and helps the teacher to realise the broader aims and objectives of education.