Author Question: The impurity of a group of observations is based on the variance of the outcome value for the ... (Read 60 times)

fox

  • Hero Member
  • *****
  • Posts: 540
The impurity of a group of observations is based on the variance of the outcome value for the observations in the group for
 a. regression trees. b. time-series plots.
  c. classification trees. d. cumulative lift charts.

Question 2

In which of the following scenarios would it be appropriate to use hierarchical clustering?
 a. When the number of observations in the dataset is relatively high.
  b. When it is not necessary to know the nesting of clusters.
  c. When the number of clusters is known beforehand.
  d. When binary or ordinal data needs to be clustered.



huda

  • Sr. Member
  • ****
  • Posts: 304
Answer to Question 1

a
RATIONALE: For regression trees, the impurity of a group of observations is based on the variance of the outcome value for the observations in the group.

Answer to Question 2

d
RATIONALE: If one has a small data set and want to easily examine solutions with increasing numbers of clusters, one may want to use hierarchical clustering. Hierarchical clusters are also convenient if one want to observe how clusters are nested. k-means clustering partitions the observations, which is appropriate if trying to summarize the data with k average observations that describe the data with the minimum amount of error. Because Euclidean distance is the standard metric for k-means clustering, it is generally not as appropriate for binary or ordinal data for which an average is not meaningful.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.

Did you know?

The average human gut is home to perhaps 500 to 1,000 different species of bacteria.

Did you know?

A strange skin disease referred to as Morgellons has occurred in the southern United States and in California. Symptoms include slowly healing sores, joint pain, persistent fatigue, and a sensation of things crawling through the skin. Another symptom is strange-looking, threadlike extrusions coming out of the skin.

Did you know?

Famous people who died from poisoning or drug overdose include, Adolf Hitler, Socrates, Juan Ponce de Leon, Marilyn Monroe, Judy Garland, and John Belushi.

Did you know?

A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.

For a complete list of videos, visit our video library