Answer: The Error Bound for Proportions (EBP) gives the maximum amount of error that can be tolerated when estimating a population proportion from a sample proportion.
To find the EBP at the 95% level, we can use the following formula:
EBP = z*(sqrt((p*(1-p))/n))
where:
z = z-score corresponding to the desired level of confidence (for a 95% confidence level, z = 1.96)
p = sample proportion (0.31, based on the survey results)
n = sample size (1379)
Substituting the given values, we get:
EBP = 1.96*(sqrt((0.31*(1-0.31))/1379))
EBP ≈ 0.0324
Rounding to four decimal places, the Error Bound for Proportions (EBP) at the 95% level is 0.0324. This means that we can be 95% confident that the true population proportion of CEOs who are extremely concerned about the availability of key skills lies within the range of (0.31 - 0.0324) to (0.31 + 0.0324), or approximately 0.2776 to 0.3424.