Pooled Prevalence Calculator – Demonstration analyses
Estimation of Beta probability distributions for specified alpha and beta
parameters
This utility calculates summary values for Beta distributions for specified values for alpha and beta parameters.
For this analysis, two estimates were calculated. The first is for a distribution with alpha = 22.99 and beta = 3.44, and the second for a distribution with alpha = 7.39 and beta = 3.13. These values correspond to the parameters estimated in the parameter estimation example. Input values and results are summarised below:
Alpha value |
Beta value |
2.5% percentile |
25% percentile |
Median |
75% percentile |
97.5% percentile |
Mean |
Mode |
Standard deviation |
22.99 |
3.44 |
0.7207 |
0.832 |
0.8792 |
0.9176 |
0.9668 |
0.8698 |
0.9001 |
0.0642 |
7.39 |
3.13 |
0.41 |
0.6144 |
0.7157 |
0.804 |
0.9228 |
0.7025 |
0.75 |
0.1347 |
Density curves for the two distributions are:
and: