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expand range of behaviours .
improve accuracy on tasks .
improve speed.
Why not program a solution ?
cannot anticipate all possible situations .
cannot anticipate all changes over time .
no idea how to program a solution .
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sunny , cloudy or rainy .
tomorrow 's temperature
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T t
input target
features features .
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(B)
''
y
( D)
\ → CA)
→ cc )
0
Which function is the correct one ? No perfect answer.
All curves can be justified as the correct one from some perspective.
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Simplest explanation usually correct
bias Var trade
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←
high high
bias variance
X
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4111*1%44%4"
14/11/11
"""
"""
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