The "would" is conditional, not a past "would".
But in a sense it can be a past imaginary situation. It occurs in the context of something like:
"If you hadn't told me differently, I would have thought ... " This is past. But you have been told differently.
"If I hadn't seen the statistics myself, I would have thought ..." Past imaginary. But you have seen the statistics.
"I would have thought ..." implies that something has made you question whether it is still the case.
You could think of it as, "If X hadn't happened, I would still be thinking (present) that ..."
Hi, someone wanted me to upload entire paragraph so there are below.
I can't understand what "would ensure" means. I think it should be like "tips would increase with the cost of living"
Could you explain shortly?
I've noticed that some of my friends tip as much as 50 percent. Even new tipping "apps" have calculation options up to 50 percent. I thought that, if the service was outstanding, 20 percent was more than generous. Am I behind the times or just a cheapskate? Your friends are very generous to people who are woefully underpaid. And as employers knowingly underpay them, expecting the customers to make up the difference, everyone in the industry has an interest in raising the rates. I would have thought that using percentages to calculate tips would ensure increases with the cost of living. However, as you know, the usual rate has crept up to 20 percent, with something more or less depending on the type of establishment. She has no wish to discourage additional largesse. But the heart and the wallet dictate that, not by etiquette.
I'll have one more go, then someone else will have to try; or you can wait til you grow into an understanding.
So, the author has all this additional information. Without it, she "would think" something. Now, she has been put right, but is still not entirely convinced.
A: "I'm going to study Social Work."
B: "But you don't like people. I would have thought you'd go into computers or science." That is, B is saying that, without the information given by A, she would think/would have thought, that A would do science. She is possibly still not convinced. But she can't say "I would think" or "I think", because she has just been told otherwise. She means, "If you had not told me that, I would have thought (if I had bothered to think about it at all [another conditional]) you'd do science."
Over to others.