# How it works

- [HDI+ROPE (with minimum precision)](/cloud/v0.22.0/probabilistic-model-evaluation/how-it-works/hdi+rope-with-minimum-precision.md): This page explains Bayesian HDI+ROPE decision rule (with minimum precision).
- [Getting Probability Distribution of a Performance Metric with targets](/cloud/v0.22.0/probabilistic-model-evaluation/how-it-works/getting-probability-distribution-of-a-performance-metric-with-targets.md): This page describes how NannyML estimates probability distribution of a performance metric when the targets are available.
- [Getting Probability Distribution of Performance Metric without targets](/cloud/v0.22.0/probabilistic-model-evaluation/how-it-works/getting-probability-distribution-of-performance-metric-without-targets.md): This page describes how NannyML estimates the probability distribution of a performance metric when targets are not available.
- [Getting Probability Distribution of Performance Metric when some observations have labels](/cloud/v0.22.0/probabilistic-model-evaluation/how-it-works/getting-probability-distribution-of-performance-metric-when-some-observations-have-labels.md): This page describes how NannyML estimates probability distribution of a performance metric when some observations have labels while other don't.
- [Defaults for ROPE and estimation precision](/cloud/v0.22.0/probabilistic-model-evaluation/how-it-works/defaults-for-rope-and-estimation-precision.md): This pages explains how NannyML calculates default values for ROPE and precision.