Validity and reliability in research pdf

The type of questionsВ included in the question paper, time, and marks allotted. It is about the validity of the appearance of a test or procedure of the test. It indicates that a test has high content validity. It shows whether all the aspects of the test/measurement are covered.ДЄ language test is designed to measure the writing and reading skills, listening, and speaking skills. If there is a lot of difference in results, then the inter-term reliability of the test is low. The results of the same tests are split into two halves and compared with each other. It measures the consistency of the measurement. If results are the same, then the parallel-forms reliability of the test is high otherwise, itвЂ™ll be low if the results are different. The tests could be written and oral tests on the same topic. Suppose the same researcher conducts the two different forms of tests on the same topic and the same students. It includes different forms of the same test performed on the same participants. It shows that the questionnaire has low inter-rater reliability. Suppose five researchers measure the academic performance of the same student by incorporating various questions from all the academic subjects and submit various results. It measures the consistency of the results at the same time by different raters (researchers) If you get the same response from a various group of participants, it means the validity of the questionnaire and product is high as it has high test-retest reliability. Suppose a questionnaire is distributed among a group of people to check the quality of a skincare product and repeated the same questionnaire with many groups. It identifies whether the results are the same after repeated measures. It measures the consistency of the results at different points of time. Students who failed in the pre-final exam are likely to get passed in the final exams they might be more confident and conscious than earlier.Д¬hoosing comparison groups without randomization.ДЄ group of trained and efficient teachers is selected to teach children communication skills instead of randomly selecting them.Дue to the extension of the time of the experiment, participants may leave the experiment.Дue to multi-tasking and various competition levels, the participants may leave the competition because they are dissatisfied with the time-extension even if they were doing well. Groups selected depending on the extreme scores are not as extreme on subsequent testing. Participants of the first experiment may react differently during the second experiment.Д¬hanges in the instrumentвЂ™s collaborationД¬hange in the research questionВ may give different results instead of the expected results. The results of one test affect the results of another test.

The influence on the independent variable due to passage of time.Дuring a long-term experiment, subjects may feel tired, bored, and hungry. If you feel the increased weight of your experiment participants is due to lack of physical activity, but it was actually due to the consumption of coffee with sugar. Unexpected events during the experiment that are not a part of treatment. However, it was showing consistent results, but it cannot be considered as reliable. It isnвЂ™t easy to interpret the real situation.Д®xample:В If the weighing scale shows the same result, letвЂ™s say 70 kg each time, even if your actual weight is 55 kg, then it means the weighing scale is malfunctioning. Most of the time, validity is difficult to measure even though the process of measurement is reliable.

If you get the same response from various participants, it means the validity of the questionnaire and product is high as it has high reliability. Hence you are getting inaccurate or inconsistent results that are not valid.Д®xample:В Suppose a questionnaire is distributed among a group of people to check the quality of a skincare product and repeated the same questionnaire with many groups. Your weighing machine might be malfunctioning.В It means your method had low reliability. In contrast, if a method is not reliable, itвЂ™s not valid.Д®xample:В Your weighing scale shows different results each time you weigh yourself within a day even after handling it carefully, and weighing before and after meals. If a method is reliable, then itвЂ™s valid. If the method of measuring is accurate, then itвЂ™ll produce accurate results. If the results are accurate according to the researcherвЂ™s situation, explanation, and prediction, then the research is valid. Validity shows how a specific test is suitable for a particular situation. Validity refers to the accuracy of the measurement.

Validity and reliability in research pdf