mean (s.d.) mean (s.d.) size Intervention 55 4.40 0.94 5.42 (1.13) 1.02 = 0.14 d Control 53 4.26 (0.96) 5.11 (1.34) 0.85 The anova results (appendix 28) show the effect of time (factor 1) was very highly significant (F(1,106) = 208.798; <0.001), but that the interaction of time and group p was not statistically significant (F(1,106) = 3.113; = 1.713). The test of the mean p post-mean scores was also non-significant (t = 1.279; = 106; one-tailed = 0.102). df p By Cohen et (2007: 521) categorisation, this effect size is However, I al.’s “weak”. return to (2008: 254) observation that standard deviations is Wiliam’s “0.3 ... approximately the average progress in achievement made by a pupil in a year”, [referring to an educational setting] an effect size of 0.1 or even 0.05 [can be] “and This places the effect size of these parallel cohorts into a substantively useful”. positive light. Once again, the result is statistically non-significant, but an effect is shown. Table 4.16: 95% confidence interval of effect size, phase 3 Lower Actual Higher -0.13 0.14 0.63 Table 4.16 identifies the upper and lower ranges of the 95% confidence interval, using ClinTools (2012). These mirrored closely those of the RCT. The values of the confidence interval straddle 0, and so, as in phase 1, it was not possible to be 95% certain that, were my study to be repeated, an effect would be present.
size mean (s.d.) mean (s.d.) Intervention 55 4.40 0.94 5.42 (1.13) 1.02 d = 0.14 Control 53 4.26 (0.96) 5.11 (1.34) 0.85 The anova results (appendix 28) show the effect of time (factor 1) was very highly significant (F(1,106) = 208.798; p <0.001), but that the interaction of time and group was not statistically significant (F(1,106) = 3.113; p = 1.713). The test of the mean post-mean scores was also non-significant (t = 1.279; df = 106; one-tailed p = 0.102). By Cohen et al.’s (2007: 521) categorisation, this effect size is “weak”. However, I return to Wiliam’s (2008: 254) observation that “0.3 standard deviations is approximately the average progress in achievement made by a pupil in a year”, ... “and [referring to an educational setting] an effect size of 0.1 or even 0.05 [can be] substantively useful”. This places the effect size of these parallel cohorts into a positive light. Once again, the result is statistically non-significant, but an effect is shown. Table 4.16: 95% confidence interval of effect size, phase 3 Lower Actual Higher -0.13 0.14 0.63 Table 4.16 identifies the upper and lower ranges of the 95% confidence interval, using ClinTools (2012). These mirrored closely those of the RCT. The values of the confidence interval straddle 0, and so, as in phase 1, it was not possible to be 95% certain that, were my study to be repeated, an effect would be present.
AAA_EdD_-_THE_WHOLE_THING_%28post_viva%29.docx