At the test level, these metrics provide a comprehensive view of student performance and the reliability of the assessment. The metrics are:
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Students Enrolled - The total number of students who were enrolled in the test.
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Students Submitted - The total number of students who successfully submitted the test.
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Score Standard Deviation - Measures the variability of scores around the mean. A higher value signifies greater variability in scores, visually represented in the Total Score Distribution graph.
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Minimum Score - The minimum score obtained on the test.
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Mean Score - The mean score obtained on the test.
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Maximum Score - The maximum score obtained on the test.
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Cronbach's Alpha - This metric measures the internal consistency of a test, specifically how well a set of test questions work together to assess a single, unified concept. The value of Cronbach's Alpha should range between 0 and 1. A value of 0.7 or higher is generally considered acceptable, indicating good internal consistency.
However, if a test is designed to measure multiple distinct skills or concepts, a lower Cronbach's Alpha is expected. For example, a math test focusing solely on algebra would typically exhibit a higher Cronbach's Alpha than an entrance exam measuring diverse skills like language comprehension, logical reasoning, and spatial awareness.
A value close to 0 indicates no consistency among the test items. While theoretically possible, a negative Cronbach's Alpha suggests severe problems with the test questions, requiring immediate review. https://en.wikipedia.org/wiki/Cronbach%27s_alpha