Worksheet 26: Nearest Neighbors#

Your name:

Your student ID number:

1. Your high school friend has just moved to the bay area. Your roommate wants you to set them up on a date. How do you decide if they will be compatible?

2. What would your $1$-nearest-neigbhor prediction be for the point $x_{new}$ be? What would your $2$-nearest-neighbor prediction be?

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3. What do you notice about the $k$-nearest neighbor model prediction as $k$ increases? Do you see a disadvantage to taking $k$ too small? Do you see a disadvantage to taking $k$ too large?

4. Assume that only one example data point has features $x_i$. If $k=1$, what will $\hat{y}=f(x_i)$ be?

5. Brainstorm as many advantages and disadvantages as you can for using $k$-nearest neighbors vs. linear regression.