Question

Data Analysis & Visualization subject

Question 1. What does "R is a vectorized language" mean?

Question 2. What is unexplainable variance?

Question 3. What is confusion matrix?

A) What is model precision in a confusion matrix?
B) What is model recall in a confusion matrix?

C) Consider the following confusion matrix of daily movements of a stock market.

		ACTUAL
		Down	Up
PREDICTED	Down	30	30
	Up	70	110

i) Compute the precision of the model.
ii) Compute the recall of the model.
iii) What percentage of daily movements have been correctly predicted by the model?

Answer 1

What does "R is a vectorized language" mean?

It means that each mathematical function and operator works on a set of data rather than a single scalar value as traditional computer language do.

Example: vec = 1:9

What is unexplainable variance?

Unexplained variation is the difference between each point and that line.

Example:

here y is orignal value on line and y predicted is the point which is predicted

What is confusion matrix?

definition: A confusion matrix is a table that is often used to describe the performance of a classification model (or “classifier”) on a set of test data for which the true values are known.

A) What is model precision in a confusion matrix?

precision(p) =

B) What is model recall in a confusion matrix?

Recall(r) =

c) i) Compute the precision of the model.

precision(p) =

= 0.3 ans

ii)  Compute the recall of the model.

recall(r) =

= 0.5

iii) What percentage of daily movements have been correctly predicted by the model?

Accuracy =

= = 0.58

precentage = 0.58 * 100 = 58%

/* PLEASE UPVOTE */