Lia and Elise are discussing measures of spread. Elise says the best measure of spread with which to compare data is the IQR. Lia says the best measure of spread with which to compare data sets is the standard deviation. Complete the sentences. Elise is correct if both data sets are

large

normal

skewed

small

2such as

1, 2, 3, 4

1, 2, 4, 5, 20, 300

1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 15

3Lia is correct if the data is

large

normal

skewed

small

4 such as
60, 65, 70, 75

0, 60, 70, 70, 250

0, 10, 20, 25, 55, 60, 390

Farmers know that driving heavy equipment on wet soil compresses the soil and injures future crops. here are data on the "penetrability" of the same type of soil at two levels of compression. penetrability is a measure of how much resistance plant roots will meet when they try to grow through the soil. compressed soil 2.85 2.66 3 2.82 2.76 2.81 2.78 3.08 2.94 2.86 3.08 2.82 2.78 2.98 3.00 2.78 2.96 2.90 3.18 3.16 intermediate soil 3.17 3.37 3.1 3.40 3.38 3.14 3.18 3.26 2.96 3.02 3.54 3.36 3.18 3.12 3.86 2.92 3.46 3.44 3.62 4.26 use the data, omitting the high outlier, to give a 95% confidence interval for the decrease in penetrability of compressed soil relative to intermediate soil. compute degrees of freedom using the conservative method. interval: to