To answer these questions, it is unnecessary to run a CA. Use only your knowledge of the main facts about CA.

Q1) Suppose we run CA on a data table and obtain that the first eigenvalue is 0.2.
Then, we decide to multiply all values in the table by 2. Now, what is the value of the first eigenvalue?
0.4
0.2
0
0.1

Q2) What is the value of the first eigenvalue of the CA run on the following table (which has a very particular structure)?

0
1
3
4

Q3) Suppose we calculate the Phi² on a data table and obtain a value of 1. We also know that the 1st row of the table is exclusively associated with the 2nd column.
the first eigenvalue equals 1
the first eigenvalue equals 0.5
the second eigenvalue equals 1
the second eigenvalue equals 0.5
the second eigenvalue equals 0

Q4) In CA (tick the true statement(s)),
the total inertia is equal to the sum of inertias of all the axes
the inertia of any axis is always at most 1
the percentage of inertia for an axis measures the intensity of the association between the categories of the two variables on this axis
the eigenvalue associated with an axis measures the intensity of the association between the categories of the two variables on this axis

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