Transcript 1.2 Data Classification

1-2 Data Classification
Part 1
Types of Data
Qualitative and Quantitative
• Qualitative data consists of attributes,
labels, or nonnumerical entries.
• Quantitative data consists of numerical
measurements or counts.
• You can have numerical qualitative
data.
Example 1 p11
The base prices of several vehicles are shown in the
table. Which data are qualitative data and which are
quantitative data? (Source: Ford Motor Company*)
Model
• Fusion 14 S
• F-150 XL
• Five Hundred SEL
• Escape XLT Sport
• 2007 Explorer Sport
Trac Limited
• Freestar SEL
• Crown Victoria LX
• Expedition XLT
Base Price
• $17,795
• $18,710
• $23,785
• $24,575
• $26,775
• $27,500
• $28,830
• $35,480
Example 1 TIY 1 p11
The populations of several U.S. cities are shown in the
table. Identify the contents of each data set. Decide
whether each data set consists of numerical or
nonnumerical entries. Specify the qualitative data and
the quantitative data.
City
• Cleveland, OH
• Detroit, MI
• Houston, TX
• Las Vegas, NV
• Portland, OR
• Topeka, KS
Population
• 452,208
• 886,671
• 2,016,582
• 545,147
• 533,427
• 121,946
Related Homework Part 1
• p15 #7-12 (#11 is debatable- why?)
Part 2
Levels of Measurement
Levels of Measurement
• The level of measurement determines
which statistical calculations are
meaningful.
• The four levels of measurement, in
order from lowest to highest, are
nominal, ordinal, interval, and ratio.
Nominal Level of Measurement
Data at the nominal level of measurement are
qualitative only. Data at this level are
categorized using names, labels, or qualities.
No mathematical computations can be made
at this level.
Example: Network Affiliates in Pittsburgh, PA
• WTAE (ABC)
• WPXI (NBC)
• KDKA (CBS)
• WPGH (FOX)
Ordinal Level of Measurement
Data at the ordinal level of measurement are
qualitative or quantitative. Data at this level can
be arranged in order, or ranked, but differences
between data entries are not meaningful.
Example: Top Five TV Programs from 2/12/07 to
2/18/07 (Source: Nielson Media Research*)
1) American Idol - Tuesday
2) American Idol - Wednesday
3) Grey’s Anatomy
4) House
5) CSI
Interval Level of Measurement
Data at the interval level of measurement can be
ordered, and you can calculate meaningful
differences between data entries. At the interval
level, a zero entry simply represents a position
on a scale; the entry is not an inherent zero.
(Inherent zero means “none.”)
Example: New York Yankees’ World Series
Victories (Years) (Source: Major League
Baseball*)
1923, 1927, 1928, 1932, 1936, 1937, 1938, 1939,
1941, 1943, 1947, 1949, 1950, 1951, 1952,
1953, 1956, 1958, 1961, 1962, 1977, 1978,
1996, 1998, 1999, 2000
Ratio Level of Measurement
Data at the ratio level of measurement are similar to
data at the interval level, with the added property
that a zero entry is an inherent zero. A ratio of two
data values can be formed so that one data value
can be meaningfully expressed as a multiple of
another.
Example: 2006 American League Home Run Totals
(by Team)
Baltimore 164
Cleveland 236
Los Angeles 159
Oakland 175
Texas 183
Boston 192
Detroit 203
Minnesota 143
Seattle 172
Toronto 199
Chicago 236
Kansas City124
New York 210
Tampa Bay 190
Example 2&3 TIY 2&3 p12-13
• Identify the level of measurement
– The final standings for the Pacific Division
of the National Basketball Association
– A collection of phone numbers
– The body temperatures (in degrees
Fahrenheit) of an athlete during an
exercise session
– The heart rates (in beats per minute) of an
athlete during an exercise session.
Related Homework Part 2
• p15-16 #1-6, 13-26 (#26- you don’t need to
justify your answer)
– Associated Press*
– National Marine Fisheries Service, Fisheries
Statistics and Economics Division*
– The New York Times*
– Yankelovich for the National Representatives
Science Foundation, American Meteorological
Society*
– National Climatic Data Center*
– U.S. House of Representatives, Office of the
Clerk*