Table 2.
Statistical Measures in Bayesian Probability
Notation/Abbreviation | Full Name | Interpretation |
---|---|---|
Prior | Prior distribution | Distribution of the effect size, as assumed prior to data collection/analysis |
Posterior | Posterior distribution | Actual distribution of the effect size after the data at hand have been analysed |
P(M) | Prior model probability | Probability of this particular statistical model being supported by the data at hand, as assumed prior to data collection/analysis |
P(M|data) | Posterior model probability | Posterior probability of this particular model being supported by the data at hand, after they have been analysed |
BF | Bayes factor | The strength of evidence in favour of a given statistical model, relative to another statistical model (see below) |
BF01 | Bayes factor 0/1 | The strength of evidence in favour of Model 0, relative to Model 1 |
BF10 | Bayes factor 1/0 | The strength of evidence in favour of Model 1, relative to Model 0 |
BF10 > 100 | ‘Extreme evidence’ favouring Model 1, relative to Model 0 | |
BF10 > 30 | ‘Very strong evidence’ favouring Model 1, relative to Model 0 | |
BF10 > 10 | ‘Strong evidence’ favouring Model 1, relative to Model 0 | |
BF10 > 3 | ‘Moderate evidence’ favouring Model 1, relative to Model 0 | |
BF10 = 1 | Model 1 and Model 0 are equally supported by the evidence | |
BF10 < 0.33 | ‘Moderate evidence’ against Model 1, relative to Model 0 (equivalent to BF01 > 3) | |
BF10 < 0.10 | ‘Strong evidence’ against Model 1, relative to Model 0 (equivalent to BF01 > 10) | |
BF10 < 0.03 | ‘Very strong evidence’ against Model 1, relative to Model 0 (equivalent to BF01 > 30) | |
BF10 < 0.01 | ‘Extreme evidence’ against Model 1, relative to Model 0 (equivalent to BF01 > 100) | |
Error% | Stability of the BF | The range of the BF over the chosen Markov chain Monte Carlo iterations, e.g. BF10 = 10 with error% = 20 means that the BF10 ranged from 8 to 12 |
95% CI | Credible interval | With 95% certainty, the true effect size lies within these bounds |