Dr. Ansari Khurshid Ahmed- Factors affecting Validity of a Test.pptx

Validity is an important characteristic of a test. A test having low validity is of little use. Validity is the accuracy with which a test measures whatever it is supposed to measure. Validity can be low, moderate or high. There are many factors which affect the validity of a test. If these factors are controlled, then the validity of the test can be maintained to a high level. In the power point presentation, factors affecting validity are discussed with the help of concrete examples.

1. Factors Affecting Validity of a Test (Illustrations) For B.Ed. Students

2. Dr. Ansari Khurshid Ahmed Associate Professor Marathwada College of Education Chh . Sambhajinagar (Aurangabad)

3. Validity of a Test “Validity is the accuracy with which a test measures whatever it is supposed to measure” . Suppose a test is constructed to measure knowledge and comprehension abilities of the students. If the test contains questions based on knowledge and comprehension abilities, then it will be a valid test but if the test contains questions based on application and other higher mental abilities or skill, then the test will not be so valid because it will not measure the abilities which the test is supposed to measure.

4. Factors Affecting Validity of a Test 1.Unclear Direction If clear cut instructions in the test paper are not given regarding what is expected in the answer then the examinee will fail to answer the question as expected by the paper setter though the examinee knows the answer. Example 1: Q. Answer the following questions. ( Wrong ) Q. Answer the following questions in about 300 words. ( Right ) Example 2: Q. Match Columns. ( Wrong ) Q. In column A names of countries are given and in Column B their Capitals are given. Match the columns according to the country and its capital. ( Right )

5. Factors Affecting Validity of a Test 2. Difficult Sentence Construction Some times student fails to understand the question only because the sentence of the question is very difficult. Example 1: Q. The philosophy of education is reflected in the process of education. Explain ( Wrong ) Q. Explain the relationship between education and philosophy.( Right ) Example 2: Q. Evaluation sharpens the process of teaching learning. ( Wrong ) Q. Explain how evaluation process is helpful in making Teaching Learning Process efficient. ( Right )

6. Factors Affecting Validity of a Test 3. Difficulty level of Question A question which is too easy or too difficult loses discrimination power and thus makes the test less valid. An easy question can be correctly answered by many students whereas if the question is very difficult then there is a chance that many students will fail to answer correctly. If a test contains such questions then many students will get same marks. This makes the measurement done by the test inaccurate as ideally no two individuals should get same marks as no two individuals are alike. Examples: Q. Evaluate the educational philosophies of any three Western philosophers. ( Difficult ) Q. Write one definition of education.( Easy )

7. Factors Affecting Validity of a Test 4. Poorly constructed Test Item An item which provides clue to the students is called as poorly constructed test item. Such items make the measurement done by the test inaccurate as the student can answer such items just by guessing without knowing the answer. Examples: Teaching is an ---------- as well as a science. i ) profession ii) art iii) job iv) service (Grammatical clue) 2. ‘student tells the definition of mass’ is the specification of -------- objective. i ) scientific attitude ii) scientific method iii) knowledge iv) inquiry attitude

8. Factors Affecting Validity of a Test 5. Use of Inappropriate Item For measuring various mental abilities like knowledge, comprehension, application etc. appropriate item should be used. Otherwise the measurement through the test will be inaccurate. Examples: Objective: Comprehension Teaching is ---------- . i ) a product ii) a process iii) both product and process iv) neither product nor process Discussion: Item 1 is memory based hence it will measure knowledge ability and not the comprehension ability of the student. Objective: Knowledge 2. ‘student tells the definition of mass’ is the specification of -------- objective. i ) comprehension ii) application iii) knowledge iv) skill Discussion: Item 2 is illustration based hence it will measure comprehension ability and not the knowledge ability of the student. Both the items are inappropriate.

9. Factors Affecting Validity of a Test 6. Inappropriate Time Limit If purpose of a test is to measure speed of response i.e. how fast student answers items, then time limit of the test should be short. If ample time is given, then the speed of response will not be measured accurately and the test will become less valid. Example: Suppose a test contains 50 objective type questions for which 50 minutes are sufficient to solve. If time limit more than 50 minutes is given then speed of response will not be measured accurately. Similarly, suppose purpose of an achievement is to measure achievement of the students then adequate time should be given to the students to write the answer to show their maximum achievement. If time given to write the answer will be short then the students will not be able to express all their achievements and thus the measurement will become inaccurate making the test less valid. Example: Suppose a test contains 5 essay type questions and the time required to answer all the questions is 2 hours. If time limit of only 1 hour is given, then the students will not be able to show all their achievements and the measurement will become inaccurate making the test less valid.

10. Factors Affecting Validity of a Test 7. Influence of extraneous factors Extraneous factor implies length of answer, language, style of expression, handwriting, method of organization of answer etc. These factors attract the examiner while assessing the papers due to which score of a student may be affected not because of the inaccuracy of the answer but because of the influence of extraneous factors. This happens generally in essay type test. Objective type test does not have this limitation. Example: Q. Discuss the role of evaluation in making teaching learning process effective and efficient. Here a student has to write a long answer. There may be two or more students answering the above question with same level of accuracy but their answer may differ with respect to handwriting, length of answer, style of expression, language, method of organization etc. In such case, the examiner may not give same marks to all the students which will reduce accuracy of the measurement.

11. Factors Affecting Validity of a Test 8. Inadequate Coverage If a test contains few questions then few topics of the syllabus will be covered while testing. Student may or may not have knowledge of the rest of the topics which have not been covered in the test. Hence we can not be sure of the accuracy of measurement done by such test. Example: Suppose a test is designed to measure achievement of the students pertaining to a unit which consists of 20 bits. For adequate coverage, there has to be question from each bit of the unit. If there will be 4 to 5 questions covering 10 to 12 bits of the unit in the test, the measurement of the achievement related to the remaining 8 to 10 bits will not be possible. The measurement done by such test will be inaccurate.

12. Factors Affecting Validity of a Test 8. Halo Effect Some times teacher creates good or bad impression about a particular student. While assessing the paper of such student the teacher may add or cut marks due to the impression about the student. This is called as Halo Effect which makes the measurement inaccurate. Example: A student is very active in the class and has good manners. The teacher may have positive impression about that child. Suppose the teacher is conducting oral test and the particular student’s performance goes unsatisfactory. The teacher gives him more marks due to the good impression about the student. Here measurement of the achievement becomes inaccurate due to Halo Effect.

13. Factors Affecting Validity of a Test 9. Question Framed in the form of Quiz Some paper setters or teachers are very smart. They twist the statement of the question to make it a quiz so as to confuse the students. Such question makes the test less valid since a student who fails to understand the question fails to write the answer correctly due to which he loses marks and the measurement becomes inaccurate. Example: Q. ‘Education and philosophy are two sides of the same coin’ Discuss. Q. ‘Textbook is a tool in the hands of an architect’ Comment on the statement. Q. ‘You can take the horse to water but can not make him drink’ Explain.