Results

Results 
In this section the results of the experiment will be presented. The data for only 14 subjects were collected in the third administration because one subject had left the country by that time.
Time and difficulty data The average length of time to read the graded reader was 56.3 minutes (s.d. 15.5) at an average rate of 104.8 words per minute. Twelve of the 15 subjects took less than 60 minutes and the remainder just over 60 minutes. The average rating of text difficulty was given as 1.5 (s.d. 0.6) which shows that the text was not difficult for the subjects. Only one subject rated the text as difficult but her results were about average on all tests.
Overall results The data in Table 4 and Figure 1 show the total scores by test over the three test administrations. The data are shown graphically in Figure 1. This is reported in detail below. Table 4: The mean scores by test type for the three test administration (Max = 25, n = 15) Administration 1 (Immediate posttest) Administration 2 (One week delay) Administration 3 (Three months delay) (n = 1 4) mean s.d. mean s.d. mean s.d. word-form recognition test 15.3 (3.3) 11.1 (5.5) 8.4 (4.3) multiple-choice recognition test 10.6 (4.0) 7.9 (5.4) 6.1 (4.2) meaning (translation) test 4.6 (3.5) 1.9 (1.7) 0.9 (1.1)
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142 Figure 1: Mean scores by test over the three test administrations (Max = 25, n = 1 5)
Word-form recognition test data Table 4 and Figure 1 show that the mean score on the word-form recognition test at the immediate post-test was 15.3 (s.d. 3.3) of the 25 items which decreased to 11.1 (s.d. 5.5) after one week and to 8.4 (s.d. 4.4) after three months. The standard deviations, as a percentage of their means, all increased over time. Table 5 and Figure 2 show the mean scores by occurrence rate of the three test times on the word-form recognition test. The mean scores decreased over time from 4.2 to 2.3 (maximum 5) over the three months for the most frequent items, and the items which occurred only once stayed about the same. The more frequent items had higher recognition rates than the less frequent items.
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143 Table 5: The mean test scores by occurrence rate for the three test administrations on the word-form recognition test (Max = 5, n = 1 5) 15 to 18 times 13 to 14 times 8 to 10 times 4 to 5 times once only Immediate post-test 4.2 4.2 4.1 2.3 0.5 One week 2.8 2.9 2.7 1.7 0.9 Three months (n=14) 2.3 2.4 2.1 1.2 1.0 Figure 2: Mean scores by occurrence rate on the word-form recognition test over time (Max = 5, n = 1 5) * n = 14 at three months Table 6 and Figure 3 compare the number of word forms which were selected correctly or selected in error. For example, the test item bettle represented the English word window and appeared in the text. However, the substitute word stoll did not represent an English word found in the text and therefore should not have been selected on the word-form recognition test. The columns "selected in error" in Table 6 indicates how often the subjects were guessing. The data by subject are shown in Appendix D. Table 6 and Figure 3 show that the mean number of incorrect substitute words selected increased from 1.3 items (8.5% of the correct score) on the immediate post-test to 2.8 items (25.2%) after
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144 one week and to 2.4 (28.5%) after three months. After correction, the mean scores were 14.0 at the immediate post-test, 8.3 after one week and 6.0 after three months. Table 6: Mean scores and number of errors on the word-form recognition test for the three test administrations (Max = 25, n = 1 5) Administration 1 (Immediate posttest) Administration 2 (One week) Administration 3 (Three months) (n = 1 4) Correct Selected in error Correct Selected in error Correct Selected in error mean 15.3 1.3 11.1 2.8 8.4 2.4
s.d. (3.3) (1.8) (5.5) (3.5) (4.3) (1.6) Adjusted means * 14.0 8.3 6.0 * These were calculated by subtracting the number of incorrect items from the number of correct items. Figure 3: The rate of correct and missed recognition on the word-form recognition test over time (Max = 25, n = 15) * n = 14 at three months
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145
Multiple-choice recognition test data The data for the multiple-choice recognition test are shown in Tables 4 and 7 and Figure 4. Table 7 shows a steady decline in mean scores from the immediate post-test of 10.4 (s.d. 4.0) to 7.9 (s.d. 5.4) after one week and to 6.1 (s.d. 4.2) after three months. Table 7 and Figure 4 show the mean scores by occurrence rate for the three test administrations. On the immediate post test, there is a drop in scores by occurrence rate from 3.6 of the 5 test items (72%) for the 15-18 group to 0.8 (16%) for words which occurred once. Similar patterns are found after one week (2.7 to 0.7) and after three months (1.9 to 0.5). The data by subject and their standard deviations can be found in Appendix E. Table 7: Mean scores by occurrence rate for the multiple-choice recognition test over time (Max = 5, n = 15) 15 to 18 times 13 to 14 times 8 to 10 times 4 to 5 times once only Immediate post-test 3.6 2.0 2.7 1.5 0.8 One week 2.7 1.6 2.0 1.0 0.7 Three months (n = 14) 1.9 0.9 1.9 0.8 0.5
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146 Figure 4: Mean scores for the multiple-choice recognition test by occurrence rate over time (Max = 5, n = 15) * n = 14 at three months
The meaning (translation) test data The mean scores for the meaning (translation) test by test time are shown in Table 4 and Figure 1. The data show a steady decline in mean scores from 4.6 (s.d. 3.5) of the 25 test items (17.6%) at the immediate post-test to 0.9 (s.d. 1.1) (3.6%) after three months. The data by occurrence rate for the three test administrations on the meaning (translation) test are shown in Table 8 and Figure 5. Table 8 and Figure 5 show an overall decline in mean scores for each of the test times. On the immediate post-test, the items which were met 15-18 times registered a mean score of 2.1 of the 5 items (42%), but after three months this had dropped to 0.3 items (6%). Words which occurred fewer than eight times registered near zero on all tests. The data by subject are shown in Appendix F.
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147 Table 8: Mean scores by occurrence rate for the three test administrations on the meaning (translation) test (Max = 5, n = 15) 15 to 18 times 13 to 14 times 8 to 10 times 4 to 5 times once only Immediate post-test 2.1 0.8 1.4 0.2 0.0 One week delay 0.5 0.3 0.9 0.1 0.1 Three months delay (n = 14) 0.3 0.0 0.6 0.0 0.0 Figure 5: Mean test scores for the meaning (translation) test by occurrence rate (Max = 5, n = 15) * n = 14 at three months A repeated measures ANOVA reveals that the three tests produce significantly different scores (F = 17.11, p < .001) at the immediate post-test. Similar figures between the tests were evident
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148 at the other two test administrations. There are also significant differences between test administration times with each test type. The word-form recognition test produced F = 35.45, p <.001, the multiple-choice test produced F = 22.00, p < .001 and the meaning (translation) test F = 15.41, p = .002.