Question

If the sample proportion is 0.65, and the standard error is 0.05, what is the 68% confidence interval

Answer 1

To calculate the 68% confidence interval, we need to take into account the sample proportion and the standard error.

The formula for calculating a confidence interval is:

Confidence interval = sample proportion ± z * standard error

Where z is the z-score corresponding to the desired level of confidence. For a 68% confidence level, the z-score is approximately 1 (since 68% falls within one standard deviation of the mean in a normal distribution).

Plugging in the values:

Confidence interval = 0.65 ± 1 * 0.05

Confidence interval = 0.65 ± 0.05

Therefore, the 68% confidence interval for a sample proportion of 0.65 with a standard error of 0.05 is 0.60 to 0.70.