Cierra Davis
8/16/2016
Written Homework 1.1 Introduction to the Practice of
Statistics (p.13#52)
1. The Principal Financial Group conducted a survey of 1172 employees in the United
States between July 28, 2010, and August 8,2010, and asked if they were cu
MEASURES OF CENTRAL TENDENCY
Measure of central tendency- describes average data value
Mean, median, mode
Arithmetic mean-determine the sum of all values of the variable in the data set and
divide by the number of operations
Population arithmetic mean
DEFINE STATS AND STATISTICAL THINKING
Statistics-science of collecting, organizing, analyzing, summarizing data (a fact or
proposition used to draw a conclusion or make a decision)
Lurking variable- A lurking variable is a variable that is not included
Stats Chapter 3.4-3.5
MEASURES OF POSITION AND OUTLIERS
Z-score: measure the number of standard deviations an observation is above or below
the mean
Unitless, mean=0, stan. dev.=1
Obtained by subtracting the mean from the data value and dividing that r
2.1 ORGANIZING QUALITATIVE DATA
Raw data-data obtained
Frequency distribution-lists categories of data and number of occurences for each
category
Relative frequency-proportion/percent of observations within a category
Formula: relative freq. = frequen