UNLOCKING THE SECRETS HIDDEN IN YOUR DATA

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Data Analysis

• UNLOCKING THE SECRETS HIDDEN IN YOUR DATA

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Why Do Data Analysis ?

• What did you see?
• Makes your data visible
• Helps find obvious patterns
• Does the data makes sense?
• Are your assumptions correct?
• Did you collect enough data?

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Why Do Data Analysis ?

• What does it Mean?
• Is there is more information in the data
• emergent behavior
• unexpected patterns
• Was the hypothesis correct ?
• Why Does it Matter?
• Draw conclusions from data
• More grass gives more rabbits
• To make your project stand out to the Challenge
  Judges
• Appears to be an improvement
• vs
• Improves the result by a specific amount

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Ways to Analyze Data

• Plotting Data
• Ways to visually understand data
• Statistics
• Makes is easier to compare data
• Mean, Median, Mode
• Makes it clear if you have NOISY data
• Range, Variance, Standard Deviation

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Ways to Analyze Data

• Derivatives (Slopes)
• Tell if changes in parameters affect data
• Parameter 2 has a greater effect than Parameter 1
• Get more information from data

Great Derivative
Slope 0.39
Slope 0.16
Slope 0.08
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Plotting Data Extracting from StarlogoTNG

• Data can be extracted from a graph
• Create a graph using the line graph piece and put
  reset clock on Setup block to clear graph
• After program is run
• Click on graph in Spaceland
• Save File Excel file

This is what you get
LETS DO IT Open Fish and Plankton !!
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Plotting Data Extracting from Netlogo

• Two ways
• 1st Way Write code to extract the data you want
  see File Output Example in the Code Examples
• Open file in setup procedure
• Create a write-to-file procedure

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Plotting Data Extracting from Netlogo

• 2nd way Extract data from Netlogo graphs
• Have Netlogo generate graph on Interface page
  (example on later slide)
• Create a setup-plot procedure and a do-plot
  procedure
• Call the setup-plot procedure in setup procedure
• Call do-plot procedure in go procedure

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Plotting Data Extracting from Netlogo

• Run model until sufficient data obtained
• (PC) Right Click on Graph/(Mac)
• Select Export
• Choose location and File name - select save
• Excel File is created Next Slide
• Contains all the information in the plot and
  input parameters used.
• Contains excess information about the plot
  (color, pen down, mode, interval)

LETS DO IT Open Rabbits Grass Weeds
10
Plotting Data Extracting from Netlogo
This is what You need
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Plotting Data Different Types of PlotsAll
plots from http//www.statcan.ca

• Pie Charts music preference
• Pets purchased at pet store

• Bar Charts preferred snacks

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Plotting Data Different Types of PlotsAll
plots from http//www.statcan.ca

• Line Graphs cell phone use
• http//www.statcan.ca

• Scatter Plots
• http//en.wikipedia.org/wiki/Scatterplot

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Plotting Data Activity in Excel
LETS DO IT

• Open File Car Data
• Insert Chart
• Select type of chart
• XY Scatter
• Select Data Range
• Highlight data to be plotted

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Plotting Data Activity in Excel

• Label each data series
• Label Graph and Axis
• Select where you want graph to be (on that page
  -worksheet or on another worksheet in same file)

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Statistics

• Statistics help you
• Summarize data
• Describe data
• Analyze data

Now it is easy to summarize, describe and
analyze the data. The blue and the pink data
have the AVERAGE value (mean) but the blue data
is NOISIER (greater standard deviation).
Therefore
Hard to describe the difference Between the two
data sets
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Statistics How to Calculate in Excel

• ,-,,/ used for addition, subtraction,
  multiplication and division.
• Each cell has a label based on the column and
  row.
• Use cells to perform calculations instead of
  numbers. Example (A4B4)/C4
• Perform calculations on an entire column - copy
  and paste the equation .Warning this changes
  the cell number for each line.
• Fix a specific cell - use the symbol, example
  (A4B4)/C1
• Excel has many built in statistical functions
• Makes life easy!

E1
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Statistics Measurements of Central
TendencyMean (Average), Median, and Mode

• Definitions
• Mean (Average) Sum divided by the number of
  data points
• Median Middle data point when arranged from
  highest to lowest
• Mode Most frequent value
• Use data set to calculate Mean (Average) Median,
  Mode, Max and Min
• Select Cell where you want the value of the
  function to appear
• Select Insert then Function
• Select Statistical
• Select function wanted (AVERAGE, MEDIAN, or MODE)
  then hit OK
• Select Range of data you want to analyze by
  clicking on range symbol and highlighting range.
  Hit enter or OK

LETS DO IT StarlogoTNG Fish and Plankton
Netlogo Rabbits and Grass
18
Statistics Measurements of Data SpreadRange,
Variance and Standard Deviation

• Definitions
• Range maximum - minimum
• Variance measures noise of the data around the
  mean value.
• Standard Deviation (S) is the square
• root of the variance. Most commonly
• used measure of spread (same units
• as the data). Another reason to use S
• 68 of the data are in the interval
• Mean S to Mean S
• 95 of the data are in the interval
• Mean 2 S to Mean 2 S
• 99 of the data are in the interval
• Mean 3 S to Mean 3 S
• EXCEL does it for you!!!

LETS DO IT StarlogoTNG Fish and Plankton
Netlogo Rabbits and Grass
19
Derivatives

• What are Derivatives?
• A simple calculation using data
• Instantaneous rate of change
• SLOPE
• Why use Derivatives?
• Get more information from data
• More Ways to comparison data
• Car moving down a road
• Data the distance traveled
• Velocity the 1st derivative
• of distance
• Acceleration 2nd derivative of
  distance
• the 1st derivative of
  velocity

Slope of distance
Slope of velocity
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How to Calculate a Derivative

• Mathematically
• x position
• t time

• In Excel

You Dont Have To Use This
Use this in Excel
LETS DO IT StarlogoTNG Fish and Plankton
Netlogo Rabbits and Grass