95% confidence interval using confint()

If I'm being asked for a CI of 95%, how do I calculate a 95% confidence interval when R output gives the values for 2.5% and 97.5%?

Do I need to subtract the two values in order to obtain the 95% CI?
Or do I need to include something like ci = 0.95 for a 95% and not a 2 and 97%

confint does give you a 95% confidence interval by default.

Check out the docstring for confint. By default, the level parameter is set to a 95% confidence interval. A confidence interval is just that; an interval. By definition, intervals have two end points, and with the default endpoints, that means that your true parameter estimate will fall inside the interval given by confint 95% of the time. Check out this link for a more fully fleshed out explanation.

That is a 95% interval - the 95% interval is the area between the points in the distribution. Note that 97.5-2.5=95

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