Chapter 2 Flashcards
1
Q
Name the three attributes:
A
1) continuous
2) discrete
3) binary
2
Q
Name the 3 attribute types:
A
1) nominal - non ordered only uniqueness matters
2) Ordinal - order matters but values can’t be directly related
3) interval - ordered and relative magnitude has specific meaning, zero does not have meaning
4) Ratio - if zero has meaning - twice as large makes sense.
3
Q
When to use mean/sd normalization
A
When variables are on different scales
4
Q
When is it good to apply log-transform?
A
WHen we have to make computer respect scale - eg differencein weights between mouse and elephant.
5
Q
Why is one-out-of-k encoding preferable for ordinal variables?
A
It does notput weights on the values.
