Step 1: Understanding residuals.
In regression analysis, a residual is the difference between the observed value of the dependent variable and the value predicted by the model. It represents the error in the model's predictions.
Step 2: Analysis of options.
- (A) Fraction of all the test data's variance that is accounted for by the model: Incorrect, this describes the R-squared value, not residuals.
- (B) The difference between the value predicted for a data point and the actual observed value: Correct, this is the definition of a residual.
- (C) A regression method where we tune our model parameters so as to minimize sum of the distances between data points: Incorrect, this refers to techniques like least squares, but not residuals.
- (D) Actual predicted value: Incorrect, the predicted value is the value the model forecasts, not the residual.
Step 3: Conclusion.
The correct answer is (B) The difference between the value predicted for a data point and the actual observed value.
Find the least upper bound and greatest lower bound of \( S = \{X, Y, Z\} \) if they exist, of the poset whose Hasse diagram is shown below:
Suppose \( D_1 = (S_1, \Sigma, q_1, F_1, \delta_1) \) and \( D_2 = (S_2, \Sigma, q_2, F_2, \delta_2) \) are finite automata accepting languages \( L_1 \) and \( L_2 \), respectively. Then, which of the following languages will also be accepted by the finite automata:
(A) \( L_1 \cup L_2 \)
(B) \( L_1 \cap L_2 \)
(C) \( L_1 - L_2 \)
(D) \( L_2 - L_1 \)
Choose the correct answer from the options given below: