If all possible values of z (predictions from linear regression) are negative, then if we use a threshold of 0.5, wouldn’t logistic regression always predict y=0?

I’m assuming in this case we would have to change the threshold. I’m just unsure because Andrew only ever mentions a threshold of 0.5 in the video and lab and also gave this as a rule:

```
As you can see, 𝑔(𝑧)>=0.5 for 𝑧>=0
For a logistic regression model, 𝑧=𝐰⋅𝐱+𝑏 . Therefore,
if 𝐰⋅𝐱+𝑏>=0 , the model predicts 𝑦=1
if 𝐰⋅𝐱+𝑏<0 , the model predicts 𝑦=0
```

Any clarification would be appreciated