The question: I'm wondering if anyone knows of a way to obtain a confidence interval on a probability estimates obtained from a model (e.g., from a logistic regression model or a neural network) in a binary class prediction setting (i.e., the model only outputs a probability prediction that is then used to decide whether the predicted class will be positive or negative)?
Some additional information: Conformal prediction provides a way to obtain a set of predictions $\tau(\mathbf{x})$ for a test instance $\mathbf{x}$ in a multi-class classification setting, where the prediction set has a probability of 1-$\alpha$ of containing the true class label. The process of obtaining this set involves a so-called calibration set $D = \{(\mathbf{x}_1,y_1),\dots,(\mathbf{x}_n,y_n)\}$ and a conformity measure $S$. Using $D$ and $S$, a value $\hat{q}$ is found such that the conformity score for each class $k=1,\dots,K$ obtaine from a model $f$ on a test instance $\mathbf{x}$ produces the prediction set with a $1-\alpha$ confidence. I.e., $\tau(\mathbf{x}) = \{k|S(f(\mathbf{x})_k) \geq \hat{q}:k=1,\dots,K \}$.
The problem: Conformal prediction provides a class prediction set and is most useful in a multi-class classification setting. I'm wondering if there's a way to take the idea of conformal prediction (or some other idea if necessary/applicable) and to, instead, obtain a confidence interval on a predicted probability?
Put differently (and this may be why this "sort of" a weird ask): I want a confidence interval on a probability estimate such that the probability interval contains the "true probability" with 95% confidence. I know this is a weird question because, in practice, we never observe "true" probabilities, but only the known outcomes -- i.e., we only observe when the probability becomes 100% when the even occurs, and only observe that it has "not yet occurred" in the case of the negative class samples.