Statistics with Stiles

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Statistics with Stiles
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Hello Favorite Class! Write down the number of
pennies I can drop into the cup at the front of
the room without spilling any water.

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Intuition vs. Empiricism

• Intuition- understanding without apparent effort,
  quick and ready insight seemingly independent of
  previous experiences or empirical knowledge. (gut
  feeling)

• Empiricism emphasizes the role of experience and
  evidence .

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Would anyone like to volunteer to win some money?



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Envelope Demo Explained

• Movie scenes explain the stats problem.

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Lets Test This Statistical Strategy!

• Class Wide Data Gathering Demo

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Descriptive vs. Inferential

• Descriptive
• Summarizes a set of data, makes it easy to
  interpret.
• , averages
• r correlation coefficient
• Standard Deviation

• Inferential
• Allows us to make decisions or reach conclusions
  about data.
• Statistically Significant or Chance? (p lt .05)
• The probability of an event occurring by chance
  is less than 5.

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Measures of Central Tendency

• Mode- most frequent
• Median- middle most
• Mean- average of set scores
• Frequency distributions-(organized list)
• Can be misleading, know which measure of average
  is being used.

Positive/Negative Skew ?
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Measures of Variability

• Range- difference in high/low
• Standard Deviation- square root of variance
  (measure of variance from the mean)
• Packed together or dispersed?

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(No Transcript)
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Using Standard Deviation to your Advantage!Top
10 Rushing Leaders (2000)
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Ranked Order of Rushers

• Who is the most consistent?
• Davis
• Who is the most erratic?
• Dillon

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Correlations (Co-relation)

• r -1.0 (strong negative correlation)
• ??
• r 1.0 (strong positive correlation)
• ?? or ??
• 0 No Correlation

• Correlation coefficients help us determine the
  direction and strength of a relationship.
• Correlation does NOT imply causation!!
• Correlations may be used to predict!

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Identify each of the scatter plots.r -.99
r -.7 r 0 r -.3 r
.5 r .9
Scatter Plot A
Scatter Plot B
Scatter Plot C
Scatter Plot D
Scatter Plot E
Scatter Plot F