A researcher plans to select a random sample from a population with o=20 what is the minimum sample size the researcher needs to have a standard error no greater than 2 points?

Number 16

A local DMV (location of your choice) wanted to assess the number of mistakes that were made by its operators (aka clerks).  One hundred samples were gathered from each of 20 operators (note: n = 100 for calculation of σp but you will need 100 * 20 to calculate p-bar).  The results are shown in the table below.  The DMV wants to set control limits to include 95% of the random variation.   Operator # Number of errors Fraction defective Operator # Number of errors Fraction defective 1 6   11 6   2 5   12 1   3 0   13 8   4 1   14 7   5 4   15 5   6 2   16 4   7 5   17 11   8 3   18 3   9 3   19 0   10 2   20 4       Calculate p-bar and σp.  Complete the fractions defective in chart. Compute the control limits and center line for a p-chart. Plot the fraction defective in a p-chart and decide if the performance of the operators is…

A researcher wishes to estimate the true proportion of all speeders who exceed the posted speed limit on a particular stretch of road in the Canyonlands National Park where there are frequent accidents. How large should the sample be so that with 91 percent confidence, the sample proportion will not differ from the true proportion by more than 0.261?z = n ⩾

What would be the mean of the sampling distribution of all possible sample means obtained from this population? If population with a positively skewed distribution of scores has a mean of 5 and a standard deviation of 4.

An excess of high values for the cases distributed on a graph results in a positive skew in the data?