Explain the relationship between reliability, validity, and the quality of educational decisions.
Reliability can be explained as the consistency of scores over time. Assessments are usually reliable when you get the same results regardless of when the assessment is taken or who does the scoring. On the other hand, Validity indicates how well an assessment actually measures what it is supposed to measure. Every assessment requires students to complete some task or activity and the validity of the task should reflect some knowledge or performance, and be consistent with current educational theory and practice. The quality of the assessment should be reliable because you would think that teachers thought carefully about the assessment before giving it to their students.
Describe several causes of measurement error and how such error may lead to improper interpretations of students' assessment results.
Errors are the different factors that causes that usually prevents a measurement to be reliable. One of these errors is an administration error in which the test was not administered properly or the students did not get the correct amount of time to perform the assessment. This will more or likely causes the results of the assessment to be invalid or unreliable. Another error is scoring error which will show inconsistent scoring on an assessment which therefore affects the reliability. Teachers should therefore try to keep the scoring a little more simple and consistent to avoid “improper interpretations of students' assessment results”.
EDF 3430 – Session 4Santina Ellis 9/14/13
Describe three causes of measurement error. Give brief scenarios to illustrate how each type could happen in your classroom.
According to our readings the three causes of measurement error are:
Content sampling error: Errors that come from sample of items & domain of items
This can occur in your classroom if there are differences