Exercise

# Bar plots with error

In the video, we saw how to incorporate error bars into our bar plot to give the viewer a sense of the uncertainty in our estimates. We used error bars of +/- 1 standard error, but it's also common to use +/- 2 standard errors since that roughly represents a confidence interval for the quantity of interest.

Instructions 1/2

**undefined XP**

- Add two columns to
`out`

:`lower`

where the values are**two**standard errors below the means given in`SleepHrsNight`

and`upper`

where the values are**two**standard errors above the means given in`SleepHrsNight`

.