The National Spanish Exam 2014

Reliability

NSE recognizes that test reliability is defined as the degree to which the test gives consistent results each time it is given.

In other words, reliability answers the following questions:

  1. Can I depend on the test to measure the same outcomes consistently?
  2. Given all the other variables being the same, will the test produce the same results again?

NSE uses the Kuder-Richardson 21 formula to calculate reliability coefficients:

r (reliability) = (K)(SD2)-M(K-M)(SD2)(K-1)

K = the number of items in the list
SD = the standard deviation of the scores
M = the mean of the scores

The scores of reliability are judged against a perfect score of 1.00. The closer the reliability coefficient is to 1.00, the better it is. Most standardized tests usually have a reliability coefficient of .90 or above.1

Reliability Coefficients

for the 2014 National Spanish Exam

Level 01 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=5560)
  Mean Raw Score 61.0 51.0 112.0 63.4 53.5 116.9 228.9
  Standard Deviation 17.5 18.4 33.1 19.9 20.6 37.1 65.2
  Reliability coefficient 0.931 0.936 0.960 0.951 0.951 0.970 0.979
Outside Experience (N=1413)
  Mean Raw Score 71.7 55.9 127.6 70.8 63.4 134.2 261.8
  Standard Deviation 16.8 19.1 33.0 19.8 22.2 39.0 66.7
  Reliability coefficient 0.938 0.942 0.962 0.957 0.963 0.976 0.982
Bilingual (N=457)
  Mean Raw Score 87.6 66.4 154.0 75.7 72.2 147.9 301.9
  Standard Deviation 14.1 17.5 28.3 19.4 22.4 39.2 59.6
  Reliability coefficient 0.955 0.936 0.961 0.961 0.970 0.980 0.982

Level 1 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=37218)
  Mean Raw Score 65.9 55.7 121.6 69.1 58.1 127.2 248.9
  Standard Deviation 18.0 19.6 35.2 20.7 21.9 39.4 69.9
  Reliability coefficient 0.940 0.945 0.966 0.960 0.959 0.975 0.983
Outside Experience (N=3731)
  Mean Raw Score 77.0 64.3 141.3 77.7 71.7 149.4 290.7
  Standard Deviation 16.6 18.6 32.7 18.3 21.6 37.1 65.4
  Reliability coefficient 0.945 0.943 0.966 0.958 0.966 0.977 0.984
Bilingual (N=1963)
  Mean Raw Score 85.7 66.8 152.6 78.8 75.5 154.3 306.9
  Standard Deviation 16.1 18.7 31.8 20.2 22.3 40.2 65.5
  Reliability coefficient 0.962 0.946 0.969 0.969 0.973 0.983 0.986

Level 2 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=35596)
  Mean Raw Score 50.8 39.1 89.9 71.4 56.4 127.8 217.7
  Standard Deviation 17.3 19.5 33.6 19.9 21.6 37.7 65.1
  Reliability coefficient 0.926 0.947 0.961 0.958 0.957 0.972 0.979
Outside Experience (N=2841)
  Mean Raw Score 62.5 46.0 108.5 76.3 65.8 142.1 250.6
  Standard Deviation 19.2 19.9 35.3 19.0 21.8 37.3 65.8
  Reliability coefficient 0.946 0.947 0.965 0.960 0.962 0.975 0.981
Bilingual (N=2637)
  Mean Raw Score 79.9 56.4 136.3 78.4 71.1 149.5 285.8
  Standard Deviation 19.3 19.7 36.3 19.2 21.6 37.7 64.9
  Reliability coefficient 0.967 0.946 0.972 0.964 0.966 0.978 0.983

Level 3 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=28858)
  Mean Raw Score 54.9 49.7 104.6 68.1 58.5 126.6 231.2
  Standard Deviation 18.0 19.5 34.1 18.4 19.7 34.2 61.4
  Reliability coefficient 0.933 0.944 0.962 0.945 0.947 0.965 0.977
Outside Experience (N=2452)
  Mean Raw Score 64.6 54.6 119.3 70.9 64.6 135.6 254.8
  Standard Deviation 20.5 20.4 37.4 19.2 20.5 36.2 66.2
  Reliability coefficient 0.955 0.950 0.970 0.953 0.955 0.972 0.981
Bilingual (N=2674)
  Mean Raw Score 85.1 66.9 151.9 74.6 67.6 142.1 294.1
  Standard Deviation 18.6 19.1 35.2 19.3 20.4 36.3 61.4
  Reliability coefficient 0.973 0.949 0.975 0.959 0.957 0.974 0.982

Level 4 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=16380)
  Mean Raw Score 53.9 45.8 99.8 62.0 55.3 117.3 217.1
  Standard Deviation 17.4 19.6 32.8 18.7 19.5 34.4 60.4
  Reliability coefficient 0.927 0.945 0.958 0.942 0.944 0.964 0.975
Outside Experience (N=1647)
  Mean Raw Score 60.2 46.9 107.1 63.1 59.8 122.8 229.9
  Standard Deviation 19.0 19.0 33.4 19.5 21.0 36.7 62.2
  Reliability coefficient 0.943 0.940 0.960 0.948 0.955 0.970 0.977
Bilingual (N=2120)
  Mean Raw Score 81.5 57.0 138.5 63.5 64.2 127.7 266.2
  Standard Deviation 18.4 17.2 32.4 20.9 22.5 39.8 60.9
  Reliability coefficient 0.965 0.926 0.964 0.957 0.964 0.976 0.978

Level 5 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=5623)
  Mean Raw Score 54.8 46.8 101.6 64.6 61.2 125.7 227.4
  Standard Deviation 17.7 19.7 33.4 20.4 21.1 37.9 64.0
  Reliability coefficient 0.930 0.946 0.960 0.954 0.956 0.972 0.978
Outside Experience (N=789)
  Mean Raw Score 65.0 51.0 116.0 66.2 66.8 133.0 248.9
  Standard Deviation 19.7 20.5 36.4 19.5 19.6 35.4 62.7
  Reliability coefficient 0.951 0.950 0.968 0.950 0.952 0.969 0.979
Bilingual (N=1330)
  Mean Raw Score 81.2 60.6 141.8 62.1 64.7 126.9 268.7
  Standard Deviation 16.5 19.8 33.3 21.1 23.6 40.8 62.4
  Reliability coefficient 0.954 0.949 0.968 0.957 0.969 0.977 0.980

Level 6 Vocabulary Grammar Achievement Reading Listening Proficiency Total
Regular (N=402)
  Mean Raw Score 60.4 52.0 112.4 69.7 69.1 138.8 251.2
  Standard Deviation 18.6 19.0 33.2 19.1 18.0 33.5 58.0
  Reliability coefficient 0.940 0.940 0.960 0.951 0.944 0.967 0.975
Outside Experience (N=137)
  Mean Raw Score 74.7 59.7 134.5 73.2 74.6 147.8 282.3
  Standard Deviation 18.9 21.2 36.2 24.1 24.2 46.3 73.2
  Reliability coefficient 0.957 0.956 0.971 0.976 0.977 0.987 0.987
Bilingual (N=429)
  Mean Raw Score 86.7 66.6 153.3 63.8 67.6 131.4 284.7
  Standard Deviation 13.3 17.8 28.1 23.0 24.3 43.9 59.5
  Reliability coefficient 0.945 0.939 0.960 0.966 0.973 0.982 0.979

1John A. Kaufhold, Basic Statistics for Educational Research (New York: iUniverse, Inc., 2007) pp. 43-46.