Statistics and Models Ch. 2 Sec. 2

Using Statistics ► Statistics = collection and classification of data that are in the form of numbers.  Summarize, characterize, analyze, and compare data

Georgia Further information People MapStatsGeorgiaUSA Population, 2008 estimate 9,685,744304,059,724 Population estimates base (April 1) ,186,812281,424,602 Population, percent change, April 1, 2000 to July 1, %8.0% Population, change, April 1, 2000 to July 1, ,498,93222,635,122 Persons under 5 years old, ,42220,724,125 Persons under 5 years old, percent, %6.9% Persons under 18 years old, ,531,60973,901,733 Persons under 18 years old, percent, %24.5% Persons 65 years old and over, percent, %12.6% Persons 65 years old and over, ,83237,887,958 Female persons, percent, %50.7%

Statistics and Population ► Statistical population = group of similar things that a scientist is interested in learning about Enrollment information for Model High School

Average ► Average = mean  Mean = the number obtained by adding the data for a characteristic and dividing this sum by the # of individuals Six students scored 72, 75, 78, 82, 84, and 92 on a test. To calculate the average, add and divide the sum (483) by six. The average score would be 80.5.

Distribution ► Distribution = relative arrangement of the members of a statistical population  Pattern the bars create

Distribution ► Normal Distribution = bell-shaped curve  Group symmetrically around the mean

Probability ► Probability= the chance that something will happen Odds of winning an Olympic medal: 662,000 to 1 Odds of injury from shaving: 6,585 to 1 Odds of being struck by lightning: 576,000 to 1

Probability ► Sample size = number of objects or events sampled  Must represent population (can’t be too small or too big)

Risk ► Risk = the probability of an unwanted outcome

Models ► Models = representations of objects or systems 1. Physical 2. Graphical 3. Conceptual 4. Mathematical

Physical Models ► 3-D models you can touch and closely resemble what they represent  DNA, Globe, Cell,

Graphical Models ► Maps and charts  Position of stars, amount of forest, depth of water

Conceptual Models ► Verbal or graphical explanation of how a system works or is organized  Flow chart, diagrams

Mathematical Models ► One or more equations that represents the way a system or process works  Lots of variables cube = a 3 rectangular prism = a b c irregular prism = b h cylinder = b h = pi r 2 h pyramid = (1/3) b h cone = (1/3) b h = 1/3 pi r 2 h sphere = (4/3) pi r 3 ellipsoid = (4/3) pi r 1 r 2 r 3