The estimated spread in sample means or averages is the (true) standard error. the estimated standard error. the population standard deviation. the sample mean. the sample standard deviation, At issue is the proportion of people in a particular county who do not have health care insurance coverage and an investigator wants to estimate it with 90% confidence. A preliminary sample of 240 people were asked if they have insurance coverage and 66 replied that they did not have coverage. What sample size would be needed to achieve a margin of error of .03? 240 600 536 479 There is not enough information to answer this question. A simple random sample of 31 observations was taken from a large population that has a mean of 5.2 and a standard deviation of 1.1. From the sample, the average was calculated to be 5 and the standard deviation was computed as 0.92. The number 5.2 in this scenario is a sample mean population parameter. standard error. sample standard deviation. statistic or point estimate