Project_1.docx - MATH 114 PROJECT 1 1. Each of the...

MATH 114
P
ROJECT
1
1. Each of the following 5 data sets has a mean close to 100, and a standard deviation in the
20s. Assume that each of these are sample data sets. For each of the 5 data sets given below,
use the Excel function “=stdev.s” (or technology) to find the actual sample standard deviation
(10 points), compute the estimate given by the Range Rule of Thumb (RROT) Estimate (10
points), and compute the percentage error of the estimate (10 points). The formula for the
RROT estimate is RROT estimate = Range/4 (where the range = maximum value – minimum
value), on the assumption that the Standard Deviation

RROT estimate. The formula used
to find the percentage error of the estimate is:
% Error = | RROT Estimate – Standard deviation | / Standard Deviation × 100%.
a. Data Set 1: No outliers
78 78 78 78 78 122 122 122 122 122
Actual Standard deviation = 23.19 RROT Estimate = 11 % Error = -52%
b. Data Set 2: 1 outlier
88 88 89 89 90 90 91 91 92 170
Actual Standard deviation = 25 RROT Estimate = 20.5 % Error = -18%
Or excluding outliers
Actual Standard deviation = 1 RROT Estimate = 1 % Error = 0
Median (Q2)=90 Q1=89