Statistics Boxplots https://www.123rf.com/photo_6622261_statistics-and-analysis-of-data-as-background.html.

Slides:



Advertisements
Similar presentations
Are There Any Outliers? Using the 1.5*IQR Rule Say we have the following data: 1,2,5,5,7,8,10,11,11,12,15,20 Notice that you must have ordered data before.
Advertisements

Chapter 2 Exploring Data with Graphs and Numerical Summaries
Descriptive Measures MARE 250 Dr. Jason Turner.
Understanding and Comparing Distributions 30 min.
Measures of Variation Sample range Sample variance Sample standard deviation Sample interquartile range.
1 Distribution Summaries Measures of central tendency Mean Median Mode Measures of spread Range Standard Deviation Interquartile Range (IQR)
Starter 1.Find the median of Find the median of Calculate the range of Calculate the mode.
5 Number Summary Box Plots. The five-number summary is the collection of The smallest value The first quartile (Q 1 or P 25 ) The median (M or Q 2 or.
Box and Whisker Plots and the 5 number summary Chapter 6 Section 7 Ms. Mayer Algebra 1.
Vocabulary for Box and Whisker Plots. Box and Whisker Plot: A diagram that summarizes data using the median, the upper and lowers quartiles, and the extreme.
The Five Number Summary and Boxplots
Continued… Obj: draw Box-and-whisker plots representing a set of data Do now: use your calculator to find the mean for 85, 18, 87, 100, 27, 34, 93, 52,
1 Further Maths Chapter 2 Summarising Numerical Data.
Box and Whisker Plots and the 5 number summary Mr. J.D. Miles Turner Middle School Atlanta Georgia
Box and Whisker Plots. Introduction: Five-number Summary Minimum Value (smallest number) Lower Quartile (LQ) Median (middle number) Upper Quartile (UP)
Chapter 5: Boxplots  Objective: To find the five-number summaries of data and create and analyze boxplots CHS Statistics.
1 Chapter 2 Bivariate Data A set of data that contains information on two variables. Multivariate A set of data that contains information on more than.
Box and Whisker Plots and the 5 number summary Mr. J.D. Miles Turner Middle School Atlanta Georgia
Box Plots March 20, th grade. What is a box plot? Box plots are used to represent data that is measured and divided into four equal parts. These.
Foundations of Math I: Unit 3 - Statistics Arithmetic average Median: Middle of the data listed in ascending order (use if there is an outlier) Mode: Most.
5-Number Summary A 5-Number Summary is composed of the minimum, the lower quartile (Q1), the median (Q2), the upper quartile (Q3), and the maximum. These.
Probability & Statistics Box Plots. Describing Distributions Numerically Five Number Summary and Box Plots (Box & Whisker Plots )
Example - Fax Here are the number of pages faxed by each fax sent from our Math and Stats department since April 24 th, in the order that they occurred.
Probability & Statistics
Box and Whisker Plots or Boxplots
5-Number Summaries, Outliers, and Boxplots
Get out your notes we previously took on Box and Whisker Plots.
Welcome to Week 04 Tues MAT135 Statistics
Box and Whisker Plots and the 5 number summary
Box and Whisker Plots and the 5 number summary
Find the lower and upper quartiles for the data set.
STATISTICS ELEMENTARY MARIO F. TRIOLA
Exploratory Data Analysis (EDA)
Understanding and Comparing Distributions
Describing Distributions Numerically
Bar graphs are used to compare things between different groups
Understanding and Comparing Distributions
Unit 4 Statistics Review
Box and Whisker Plots Algebra 2.
2.6: Boxplots CHS Statistics
Lecture 2 Chapter 3. Displaying and Summarizing Quantitative Data
Statistics Boxplots
The absolute value of each deviation.
Approximate the answers by referring to the box plot.
Mean As A Balancing Point
Box and Whisker Plots.
Measuring Variation 2 Lecture 17 Sec Mon, Oct 3, 2005.
Measures of Central Tendency
Box-And-Whisker Plots
Define the following words in your own definition
Box & Whiskers Plots AQR.
Organizing, Summarizing, &Describing Data UNIT SELF-TEST QUESTIONS
Boxplots.
Understanding and Comparing Distributions
Statistics Fractiles
Statistics and Data (Algebraic)
Mean As A Balancing Point
Box and Whisker Plots and the 5 number summary
The Five-Number Summary
Box-And-Whisker Plots
Box-And-Whisker Plots
Box and Whisker Plots and the 5 number summary
Box and Whisker Plots.
Box and Whisker Plots and the 5 number summary
SnapChat Mini-Project
Box and Whisker Plots and the 5 number summary
Unit 2: Box Plots (Tukey) Descriptive Statistics Part Four
Cumulative Frequency and Box Plots
Number Summaries and Box Plots.
Presentation transcript:

Statistics Boxplots https://www.123rf.com/photo_6622261_statistics-and-analysis-of-data-as-background.html

Exploring Data We are using the descriptive statistics to summarize our sample (and, hopefully, our population) in just a few numbers

Exploring Data The “five-number summary” is: the min Q1 the median Q3 the max

Boxplots There is a graph statisticians use to show this summary: the box plot (or boxplot)

Boxplots The boxplot (a.k.a. box and whisker diagram) is a standardized way of displaying the distribution of data based on the five number summary: minimum, first quartile, median, third quartile, and maximum

Boxplots

BOXPLOTS IN-CLASS PROBLEM Daily high temperatures Feb 2008 for Fairbanks, Alaska: 14, 12, 17, 25, 10, -1, -8, -15, -7, 0, 5, 14, 18, 14, 16, 8, -15, -13, -17, -12, 0, 1, 9, 12, 14, 7, 6, 8 Create a Boxplot

What do we need for a Boxplot? BOXPLOTS IN-CLASS PROBLEM What do we need for a Boxplot?

BOXPLOTS IN-CLASS PROBLEM Daily high temperatures Feb 2008 for Fairbanks, Alaska: 14, 12, 17, 25, 10, -1, -8, -15, -7, 0, 5, 14, 18, 14, 16, 8, -15, -13, -17, -12, 0, 1, 9, 12, 14, 7, 6, 8 Find the 5-number summary

BOXPLOTS IN-CLASS PROBLEM Min = Q1 = Median = Q3 = Max =

BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Notice they’re all in order at the bottom of your list! YAY!

Min = -17 Now for the box! Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 BOXPLOTS IN-CLASS PROBLEM Min = -17 Now for the box! Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Min! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Min! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Q1! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Q1! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Median! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Median! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Q3! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Q3! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Max! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Max! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Box! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Box! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Whiskers! BOXPLOTS IN-CLASS PROBLEM Min = -17 Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 Whiskers! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Questions?

Outliers Because the min and max may be outliers, a variation on the boxplot includes “fences” to show where most of the data occurs

Outliers Lower fence: Q1 - 1.5 * IQR Upper fence: Q3 + 1.5 * IQR

Min = -17 What is the IQR? Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 OUTLIERS IN-CLASS PROBLEM Min = -17 What is the IQR? Q1 = -4 Median = 7.5 Q3 = 14 Max = 25 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 What is the Median = 7.5 lower fence? Q3 = 14 Max = 25 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 Lower fence = Median = 7.5 Q1-1.5*IQR Q3 = 14 -4-1.5(18) Max = 25 = -31 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 Lower fence=-31 Median = 7.5 What is the Q3 = 14 upper fence? Max = 25 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 Lower fence=-31 Median = 7.5 Upper fence= Q3 = 14 Q3+1.5*IQR Max = 25 14+1.5(18)=41 -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 Lower fence=-31 Median = 7.5 Upper fence=41 Q3 = 14 So, do we have Max = 25 any outliers? -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

OUTLIERS IN-CLASS PROBLEM Min = -17 IQR=14-(-4)=18 Q1 = -4 Lower fence=-31 Median = 7.5 Upper fence=41 Q3 = 14 Max and Min are Max = 25 inside the fence! -24 -20 -16 -12 -8 -4 0 4 8 12 16 20 24

Outliers How outliers are shown in a boxplot

Types of Boxplots

Questions?

Boxplots Boxplots are typically used to compare different groups

Data Summary Table from a Ball-bouncing Experiment Boxplots Data Summary Table from a Ball-bouncing Experiment Super Ball Wiffle Golf Splash SpongyBall Minimum 66 38 70 7 44 Q1 71 45 75 14 58 Median 76 48 78 16.5 60 Q3 50 80 23 62 Maximum 91 90 28 67

Boxplots

Boxplots

BOXPLOTS IN-CLASS PROBLEM What differences?

Boxplots Unfortunately it is almost impossible to get a true boxplot using Excel

Boxplots Unfortunately it is almost impossible to get a true boxplot using Excel (there are several YouTube videos showing how to get one…

Boxplots Unfortunately it is almost impossible to get a true boxplot using Excel (there are several YouTube videos showing how to get one… but they are all wrong…)

Questions?