APTA
Main Content

Standard Error of Measurement (SEM)

SEM refers to the standard deviation of test scores that would have been obtained from a single student had that student been tested multiple times.  It is a measure of the variation of scores that would be expected if the student had been tested repeatedly.  

Standard Error of Measuerment
Content Grade 2006 2007 2008 2009
RLA 3
5.36
5.43
5.48
5.21
4
5.65
5.31
4.85
4.89
5
5.44
5.25
4.98
5.08
6
5.03
5.44
5.44
5.30
7
5.91
6.04
5.78
5.72
8
5.93
6.81
6.87
6.71
10
5.58
5.27
4.62
11
4.40
Mathematics 3
8.61
6.09
6.37
6.07
4
7.30
6.17
6.11
5.95
5
8.21
6.64
6.52
6.28
6
7.34
6.63
6.57
6.36
7
6.35
5.98
5.80
5.66
8
8.65
7.04
6.97
6.90
10
6.44
6.01
5.94
11
5.70
Science 4  
6.21
6.57
6
6.74
7.00
11
6.39
6.21