AP Statistics Curriculum 2007 EDA Freq

From SOCR
Jump to: navigation, search

General Advance-Placement (AP) Statistics Curriculum - Summarizing data with Frequency Tables

Summarizing data with Frequency Tables & Histograms

There are two ways to describe a data set (sample from a population) - Pictorial Graphs or Tables of Numbers. Both are important for analyzing data.

Definitions

  • A frequency distribution is a display of the number (frequency) of occurrences of each value in a data set.
  • A relative frequency distribution is a display of the percentage (ratio or frequency to sample-size) of occurrences of each value in a data set.
  • A percentile is the value of a variable that divides the real line into two segments - the left one containing certain percentage (say 13%) of the observations for the specific process, and the right interval containing the complementary percentage of observations (in this case 87%). The 30th percentile is the value (measurement) bound above 30% and below 70% of the observations from a process.
  • The (three) quartiles are the special cases of percentiles for Q1=25%, Q2=50% (median) and Q3=75%.

Example

The table below shows the stage of disease at diagnosis of breast cancer in a random sample of 2092 US women.

Stage Frequency Relative Frequency
0 197 0.09
I 691 0.33
II 703 0.34
III 314 0.15
IV 187 0.09
Total 2092 1.00

Computational Resources: Internet-based SOCR Tools

  • SOCR Charts allows you to generate graphical representations (including frequency histograms) of a variety of datasets.
  • The SOCR Charts activities provide usage-instructions, examples and demonstrations of how to use SOCR Charts.

Hands-on activities

You can copy and paste the first 2 columns in the data table above in the SOCR Charts (BarChart --> XYPlot --> HistogramDemo7). You can see this SOCR Charts activity for help with histogram plots.

  • The graph below illustrates the (raw) frequency histogram (using counts)
SOCR EBook Dinov EDA 012708 Fig1.jpg
  • The graph below shows the relative frequency histogram (using the last column of the table above).
SOCR EBook Dinov EDA 012708 Fig2.jpg

Problems


References




Translate this page:

(default)
Uk flag.gif

Deutsch
De flag.gif

Español
Es flag.gif

Français
Fr flag.gif

Italiano
It flag.gif

Português
Pt flag.gif

日本語
Jp flag.gif

България
Bg flag.gif

الامارات العربية المتحدة
Ae flag.gif

Suomi
Fi flag.gif

इस भाषा में
In flag.gif

Norge
No flag.png

한국어
Kr flag.gif

中文
Cn flag.gif

繁体中文
Cn flag.gif

Русский
Ru flag.gif

Nederlands
Nl flag.gif

Ελληνικά
Gr flag.gif

Hrvatska
Hr flag.gif

Česká republika
Cz flag.gif

Danmark
Dk flag.gif

Polska
Pl flag.png

România
Ro flag.png

Sverige
Se flag.gif