In a Very Large School District, Student Records Have Been

Essay

In a very large school district, student records have been kept in three distinct data bases, one each for elementary, middle, and high school. The district now has a new data base and wishes to correct any original data entry errors. To allocate enough secretarial time to this task, an estimate of the proportion of records that contain errors must be made. Initial estimates are that there are fixable errors in about 15% of the records.
A) Using 15% as an initial estimate of the percentage of records with errors, compute the sample size required to estimate the true proportion of records with errors within .025 with 95% confidence.
B) Suppose the school district did not have an initial estimate of p . In a few sentences, explain how your procedure for choosing a samples size would differ from your solution in part (a). (Do NOT recalculate a new estimate of the necessary sample size!)