1. A prison official wants to estimate the proportion of cases of recidivism. Examining the records...

1. A prison official wants to estimate the proportion of cases of recidivism. Examining the records of 176 convicts, the official determines that there are 56 cases of recidivism.

Find the margin of error for a 99% confidence interval estimate for the population proportion of cases of recidivism. (Use 3 decimal places.)

2. A quality control engineer is interested in estimating the proportion of defective items coming off a production line. In a sample of 311 items, 45 are defective. Calculate a  90.0% confidence interval estimate for the proportion of defectives from this production line. (Use 3 decimal places in calculations and in reporting your answers.)

Lower Limit:

Upper Limit:

3. A prison official wants to estimate the proportion of cases of recidivism. Examining the records of 209 convicts, the official determines that there are 53 cases of recidivism. Find a point estimate of the population proportion of cases of recidivism. (Round your answer to three decimal places.)

4. A prison official wants to estimate the proportion of cases of recidivism. Examining the records of 297 convicts, the official determines that there are 41 cases of recidivism. Find the lower limit of the 90% confidence interval estimate for the population proportion of cases of recidivism. (Round to 3 decimal places.)

5. The head of a computer science department is interested in estimating the proportion of students entering the department who will choose the new computer engineering option. A preliminary sample indicates that the proportion will be around 0.236.

What size sample should the department head take if she wants to be 95% confident that the estimate is within 0.02 of the true proportion?

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orchestra answered 1 year ago

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