How to Calculate the Level of Confidence?
What is the level of confidence based on the survey data?
Given that 60 percent of adults in the United States are in favor of increasing the minimum hourly wage with a margin of error of 2.7 percentage points, which level of confidence is closest?
A. 80%
B. 85%
C. 90%
D. 95%
Answer:
The closest level of confidence to the data is 90%.
Calculating the level of confidence involves using a formula that takes into account the reported percentage, margin of error, and sample size.
Formula for Level of Confidence:
E = z * √(p(1-p)/n)
Where:
- E is the margin of error
- z is the z-score
- p is the reported percentage
- n is the sample size
By using the provided data and formula, we can determine that the level of confidence closest to the survey results is 90%. This is calculated by finding the z-value, which in this case is approximately 1.65, and then referencing a z-table to find the corresponding confidence level.
Therefore, with a margin of error of 2.7 percentage points, the level of confidence is 90%.