线路平面和纵断面设计.ppt

Have you ever…
Shot a rifle?
Played darts?
Played basketball?
Shot a round of golf?
What is the point of these sports?
What makes them hard?
1
Have you ever…
Shot a rifle?
Played darts?
Shot a round of golf?
Played basketball?
Emmett
Jake
Who is the better shot?
2
Discussion
What do you measure in your process?
Why do those measures matter?
Are those measures consistently the same?
Why not?
3
Variability
Deviation = distance between observations and the mean (or average)
Emmett
Jake
Observations
10
9
8
8
7
averages

Deviations
10 - =
9 – =
8 – = -
8 – = -
7 – = -

8
7
10
8
9
4
Variability
Deviation = distance between observations and the mean (or average)
Emmett
Jake
Observations
7
7
7
6
6
averages

Deviations
7 – =
7 – =
7 – =
6 – = -
6 – = -

7
6
7
7
6
5
Variability
Variance = average distance between observations and the mean squared
Emmett
Jake
Observations
10
9
8
8
7
averages

Deviations
10 - =
9 – =
8 – = -
8 – = -
7 – = -

8
7
10
8
9
Squared Deviations






Variance
6
Variability
Variance = average distance between observations and the mean squared
Emmett
Jake
Observations
7
7
7
6
6
averages
Deviations
Squared Deviations
7
6
7
7
6
7
Variability
Variance = average distance between observations and the mean squared
Emmett
Jake
Observations
7
7
7
6
6
averages

Deviations
7 - =
7 - =
7 - =
6 – = -
6 – = -

Squared Deviations






7
6
7
7
6
Variance
8
Variability
Standard deviation = square root of variance
Emmett
Jake
Variance
Standard Deviation
Emmett


Jake


But what good is a standard deviation
?
9
Variability
The world tends to be bell-shaped
Most es
occur in the
middle
Fewe