A centered dataset with n = 115 observations and p = 12 variables was analysed to reduce its dimensionality. The following is a list of singular values of X in decreasing order, that is d1, d2, ..., d12: 42.273, 10.571, 10.32, 9.818, 9.638, 9.174, 8.364, 7.834, 7.522, 7.231, 6.824, 6.086. A) Compute and write the numerical value of the eigenvalue 16 of Σ. This eigenvalue is located in the position (6,6) of the matrix A and is simultaneously the sample variance of the score PC6: B) Compute and write the percentage of total variability explained by the Principal component PC6. The number you write should be between 0 and 100 and you should include decimals in your answer. C) A threshold of total variability explained has been set at 70%. How many principal components must you select? Write your answer. D) Write the value of the variance accounted for all those principal components you selected in the previous question. E) Besides being centered, was this data scaled as well? Select. This data was centered but not scaled. This data was centered and scaled.

Algebra & Trigonometry with Analytic Geometry
13th Edition
ISBN:9781133382119
Author:Swokowski
Publisher:Swokowski
Chapter7: Analytic Trigonometry
Section7.6: The Inverse Trigonometric Functions
Problem 94E
icon
Related questions
Question
A centered dataset with n = 115 observations and p = 12 variables was analysed to reduce its dimensionality. The following is a
list of singular values of X in decreasing order, that is d1, d2, ..., d12: 42.273, 10.571, 10.32, 9.818, 9.638, 9.174, 8.364, 7.834, 7.522,
7.231, 6.824, 6.086.
A) Compute and write the numerical value of the eigenvalue 16 of Σ. This eigenvalue is located in the position (6,6) of the matrix A
and is simultaneously the sample variance of the score PC6:
B) Compute and write the percentage of total variability explained by the Principal component PC6. The number you write should be
between 0 and 100 and you should include decimals in your answer.
C) A threshold of total variability explained has been set at 70%. How many principal components must you select? Write your
answer.
D) Write the value of the variance accounted for all those principal components you selected in the previous question.
E) Besides being centered, was this data scaled as well? Select.
This data was centered but not scaled.
This data was centered and scaled.
Transcribed Image Text:A centered dataset with n = 115 observations and p = 12 variables was analysed to reduce its dimensionality. The following is a list of singular values of X in decreasing order, that is d1, d2, ..., d12: 42.273, 10.571, 10.32, 9.818, 9.638, 9.174, 8.364, 7.834, 7.522, 7.231, 6.824, 6.086. A) Compute and write the numerical value of the eigenvalue 16 of Σ. This eigenvalue is located in the position (6,6) of the matrix A and is simultaneously the sample variance of the score PC6: B) Compute and write the percentage of total variability explained by the Principal component PC6. The number you write should be between 0 and 100 and you should include decimals in your answer. C) A threshold of total variability explained has been set at 70%. How many principal components must you select? Write your answer. D) Write the value of the variance accounted for all those principal components you selected in the previous question. E) Besides being centered, was this data scaled as well? Select. This data was centered but not scaled. This data was centered and scaled.
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Algebra & Trigonometry with Analytic Geometry
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage
College Algebra
College Algebra
Algebra
ISBN:
9781337282291
Author:
Ron Larson
Publisher:
Cengage Learning
College Algebra
College Algebra
Algebra
ISBN:
9781938168383
Author:
Jay Abramson
Publisher:
OpenStax
College Algebra (MindTap Course List)
College Algebra (MindTap Course List)
Algebra
ISBN:
9781305652231
Author:
R. David Gustafson, Jeff Hughes
Publisher:
Cengage Learning
Glencoe Algebra 1, Student Edition, 9780079039897…
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781337278461
Author:
Ron Larson
Publisher:
Cengage Learning