AP StatisticsSection 1-1

Day OneTypes of Data

Bar Graphs, Pie ChartsDots Plots, Stem and leaf plots, Histograms

Homeworkp. 46 1, 2 ,4 ,5

Use Create a graph as needed

world health model

Displaying Data

Misleading Graph

Bad Graphs

Ed Tufte of Yale University has defined a “lie factor” asa measure of the amount of distortion in a graph.

Lie Factor =size of effect shown in graphic/size of effect shown in data

If the lie factor of a graph is greater than 1, the graph isexaggerating the size of the effect

THE LIE FACTOR

Look at graphs with different Lie Factors

I) Types of Data A. Categorical – a variable that places an

individual into one of several groups or categories. “Gender”, “Color”, “State”

B. Quantitative (numerical) – a variable that takes on a numerical value for which arithmetic operations and averaging make sense. “Height ”, “Temperature”

Displaying Distributions with Graphs

II) Types of Graphs A. Categorical Data – use create a graph http://nces.ed.gov/nceskids/createagraph/default.aspx

i) Pie Charts ii) Bar Graphs iii) dot plots

B. Numerical Data i) Stem and Leaf Plots

ii) Histograms iii) box plots

Example 1.1 - Radio Station Formats

Count of Percent ofFormat Stations Stations

Adult Contemporary1556 11.2Adult standards 1196 8.6Contempary hit 569 4.1Country 2066 14.9News/Talk/Information2179 15.7Oldies 1060 7.7Religious 2014 14.6Rock 869 6.3Spanish language750 5.4Other formats 1579 11.4

Total 13838 99.9

Radio Station Formats Data Set

Example 1.2 - Do you listen while you walk?

Percent Owning

Age group (years) an MP3 player

12-17 27

18-24 18

25-34 20

35-44 16

45-54 10

55-64 6

65+ 2

MP3 Player Ownership

Why Can’t you make a pie chart of this categorical data?

Dotplots*Draw an label a number line from min to max.

*Place one dot per observation above its value

* Stack multiple observations evenly.

Game Goals

1 3

2 0

3 2

4 7

5 8

6 2

7 4

8 3

9 5

10 1

11 1

12 4

Steam and Leaf Plots

Literacy Rates in Islamic Countries

Female MaleCountry Percent Percent

Algeria 60 78Bangladesh 31 50Egypt 46 68Iran 71 85Jordan 86 96Kazakhstan 99 100Lebanon 82 95Libya 71 92Malaysia 85 92Morocco 38 68Saudi Arabia 70 84Syria 63 89Tajikistan 99 100Tunisia 63 83Turkey 78 94Uzbekistan 99 100Yemen 29 70

Histograms

Divide the range of data in equal-width classes.

Count the observations in each class – “frequency”

Draw bars to represent count or percentage of observations that fall into each class.

Bars should touch (unlike bar graphs)

IQ Scores of 60 5th Graders

Example 1.6IQ Test Scores

14513912612212513096

11011811810114213412411210913411381

113

Making Calculator Histograms

1. Press and choose 1. Edit 2. Type values into list L1. 3. Set up histogram in statplot menu press (stat plot) press to go to plot1 choose on histogram X:list l1 Freq: 1 4. Press and enter appropriate bounds

Technology Toolbox

Stat

2nd y=

enter

window

SOCS !

SHAPE - roughly symmetric

skewed left skewed right, number placement of peaks (modes)

OUTLIERS – departures from pattern

CENTER - midpoint

SPREAD - minimum value

maximum value range

Shape Symmetric

Skewed

Skewed Right Skewed Left

Exploratory Data AnalysisSummary Plot your data – choose an appropriate

graph

Evaluate SOCS – shape, outliers, center , and spread