Hi!

When I summarize the statistics of my inference data using `az.summary()`

, one of the columns of the dataframe is `hdi_3%`

. A highest density interval is supposed to be a range of two values, but in the summarized data each entry of this column is one specific value. What does this value mean?

I am sorry if this is a very basic question.

Thank you in advance!

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When requesting the 94% HDI (arviz’s current default), there should be 2 columns, one representing the left end of the interval (the value below which 3% of the posterior falls) and one representing the right end of the interval (the value above which 3% of the posterior falls). So `hdi_3%`

is the former and there should be a `hdi_97%`

column with the latter.

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To just add to @cluhmann , I found the following command very handy:

```
az.hdi(trace,var_names=["XXX"], hdi_prob = 0.80).values()
```

It will print out the `hdi`

of whatever variables you want from your trace with the specified `hdi_prob`

value.

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