Question

The American Veterinary Medical Association conducted a survey of veterinary clinics to estimate the proportion that do not treat large animals (cows, horses, etc.). The survey was mailed to 120 randomly selected veterinary clinics throughout the country, and, 88 responded they do not treat large animals.

The best point estimate for a 95% confidence interval for the proportion of veterinary clinics that do not treat large animals is___.

Round your answer to the thousandths decimal place.

Answer 1

The best point estimate for a 95% confidence interval for the proportion of veterinary clinics that do not treat large animals is 0.733±0.079 i.e between

0,654 and 0.812.

Explanation:

Confidence Interval can be calculated using p±ME where

• p is the proportion that do not treat large animals (
  `(88)/(120)`=0.733)

• ME is the margin of error from the mean

and margin of error (ME) around the mean can be found using the formula

ME=
`(z*√(p*(1-p)))/(√(N) )` where

• z is the corresponding statistic in 95% confidence level (1.96)

• p is the sample proportion (
  `(88)/(120)=0.733`)

• N is the sample size (120)

Then ME=
`(1.96*√(0.733*0.267))/(√(120) )` ≈ 0.079

Then 95% confidence interval is 0.733±0.079