Split-half reliability based on continuous scores.
The split-half reliability scores for the Form G MBTI® instrument are as follows1:
EI = 82; SN = 84; TF = 83; JP = 86
The split-half reliability scores for the TPPI are as follows2:
EI = 87; SN = 93; TF = 91; JP = 85
Split-half reliability based on dichotomous scores.
EI SN TF JP
For the MBTI® instrument3: Phi 61 54 49 73
For the TPPI4: Phi 77 82 78 71
Validity Measures
Correlations between the MBTI® instrument and the TPPI5:
EI = 76; SN = 71; TF = 78; JP = 73
Summer/99
1 Based on the total Form G data bank (n=32,671) and derived from the product-moment correlation of X and Y continuous scores with Spearman-Brown prophecy formula correction. P. 166 of Manual: A Guide to the Development and Use of the Myers-Briggs Type Indicator® instrument.
2Sample of 420 (180 grade 11 and 12 high school students' lower/middle class school; 70 government office workers' mostly professional; 170 municipal workers' broad collection of backgrounds) and derived from the Spearman's rho of X and Y continuous scores with Spearman-Brown prophecy formula correction.
3Comparison of internal consistency of type categories using estimates from Phi Coefficients, all corrected using the Spearman-Brown prophecy formula. P. 171 of Manual: A Guide to the Development and Use of the Myers-Briggs Type Indicator® instrument. Based on 100 grade 12 male students.
4Comparison of internal consistency of type categories using estimates from Phi Coefficients, all corrected using the Spearman-Brown prophecy formula. Based on previously described sample of 420.
5Everyone in the sample of 420 completed both the MBTI® instrument Form G and the TPPI, therefore the Pearson Product Moment correlations are between the continuous scores of both these instruments.
*Myers-Briggs Type Indicator and MBTI are registered trademarks of Consulting Psychologists Press, Inc.