1. Statistics and Science
Statistics & Science
Statistics and Science

2. Statistics and Science
What are statistics?
Statistics is a collection, classification, and analysis of numbers.
Statistics is commonly used to describe:
Sports
Politics
Health
Weather
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Statistics and Science

3. Mean The mean is an average. Found by: Summing and then dividing
the sum by the
amount of numbers.
Example: Find the mean of: 5, 8, 2, 1
Add up the numbers:
= 16
Divide the sum by the number of scores: 4
The mean is 16 ÷ 4 = 4
Statistics and Science

4. Mean (µ) and Standard Deviation (σ)
The standard deviation is a measure of the spread relative to the mean.
Statistics and Science

5. Statistics and Science
If all the data points are clustered around
the mean, the standard deviation is low.
If the data points are widely dispersed
around the mean, the standard deviation is high.
If all the data points have the same value,
the standard deviation is zero.
Statistics and Science

6. The Normal Distribution
Bell-shaped
Large data sets
Characterized by:
mean µ
standard deviation s
Statistics and Science

7. Errors and the Normal Distribution
Measurements have random errors.
They often characterized by the normal
distribution.
Normal distribution  Probability of a given
error can be calculated.
Statistics and Science

8. Normal Probability Distribution
68% of the data within one standard deviation of the mean.
95% of the data within two standard deviations of the mean.
Statistics and Science

9. How are statistics related to science?
Science is about decision!
Statistics  standards for decisions.
Statistics and Science