Mais conteúdo relacionado Semelhante a Regression (20) Regression8. Linear regression 0 10 20 30 40 0 10 20 30 20 22 24 26 Temperature 0 10 20 0 20 40 [start Matlab demo lecture2.m] Given examples Predict given a new point 9. Linear regression 0 20 0 20 40 Temperature 0 10 20 30 40 0 10 20 30 20 22 24 26 Prediction Prediction 11. Minimize the sum squared error Sum squared error Linear equation Linear system 14. Beyond lines and planes everything is the same with still linear in 0 10 20 0 20 40 18. Assumptions vs. Reality Voltage Intel sensor network data Temperature 0 1 2 3 4 5 6 7 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 19. Overfitting 0 2 4 6 8 10 12 14 16 18 20 -15 -10 -5 0 5 10 15 20 25 30 [Matlab demo] Degree 15 polynomial 24. Sensitivity to outliers High weight given to outliers Influence function 0 10 20 30 40 0 10 20 30 5 10 15 20 25 Temperature at noon 25. L 1 Regression Linear program Influence function 30. 0 1 2 0 #requests per minute Time (days) 5000 Heteroscedasticity Notas do Editor Figure 1: scatter(1:20,10+(1:20)+2*randn(1,20),'k','filled'); a=axis; a(3)=0; axis(a); Figure 1: scatter(1:20,10+(1:20)+2*randn(1,20),'k','filled'); a=axis; a(3)=0; axis(a); Figure 1: scatter(1:20,10+(1:20)+2*randn(1,20),'k','filled'); a=axis; a(3)=0; axis(a); Link with perceptron A linear program is fast, but much slower than solving a linear system Link with kNN