John Hull Quotes

Our starting point then was trying to find a way to incorporate mean reversion into the HoLee model.

The problem with interest rates are that you are not modeling a single number, you are modeling a whole term structure, so it is a sort of different type of problem.

In the financial sector, those whom the gods want to destroy they first teach math.

Economic engineering is about the design and analysis of frameworks for achieving specific economic objectives.

Alan White and I spent the next two or three years working together on this. We developed what is known a stochastic volatility model. This is a model where the volatility as well as the underlying asset price moves around in an unpredictable way.

If you are prepared for some risk, junk bonds pay about 5%, but they tend to get whacked when interest rates rise. Same with lower-yielding but higher-quality corporate bonds.

The real challenge was to model all the interest rates simultaneously, so you could value something that depended not only on the three-month interest rate, but on other interest rates as well.

Our tree is actually a tree of the short-term interest rate. The average direction in which the short-term interest rate moves depends on the level of the rate. When the rate is very high, that direction is downward; when the rate is very low, it is upward.

We don't prognosticate macroeconomic factors, we're looking at our companies from a bottom-up perspective on their long-run prospects of returning.

The expectation of gradual policy normalization should reduce the likelihood of outsized movements in interest rates.

I have a name for people who went to the extreme efficient market theory-which is "bonkers". It was an intellectually consistent theory that enabled them to do pretty mathematics. So I understand its seductiveness to people with large mathematical gifts. It just had a difficulty in that the fundamental assumption did not tie properly to reality.

Investors should be skeptical of history-based models. Constructed by a nerdy-sounding priesthood using esoteric terms such as beta, gamma, sigma and the like, these models tend to look impressive. Too often, though, investors forget to examine the assumptions behind the models. Beware of geeks bearing formulas.

No formula in finance tells you that the moat is 28 feet wide and 16 feet deep. That's what drives the academics crazy. They can compute standard deviations and betas, but they can't understand moats.

There can be few fields of human endeavor in which history counts for so little as in the world of finance.Past experience, to the extent that it is part of memory at all, is dismissed as the primitive refuge of the those who do not have insight to appreciate the incredible wonders of the present.

I react pragmatically. Where the market works, I'm for that. Where the government is necessary, I'm for that. I'm deeply suspicious of somebody who says, 'I'm in favor of privatization,' or, 'I'm deeply in favor of public ownership.' I'm in favor of whatever works in the particular case.

First, those who disagree with market efficiency simply assert that it stands to common sense that greater effort to get facts and greater acumen in analyzing those facts will pay off in better performance somehow measured. (By this logic, cure for cancer must have been found by 1955).

The analysis in the era of Ronald Reagan and Margaret Thatcher was that government was interfering with the efficiency of the economy through protectionism, government subsidies, and government ownership. Once the government "got out of the way," private markets would allocate resources efficiently and generate robust growth. Development would simply come.

I think the Chinese are really amateurs when it comes to running markets.

I disagree with the followers of Marx and those of Adam Smith: the reason free markets work is because they allow people to be lucky, thanks to aggressive trial and error, not by giving rewards or "incentives" for skill.

In fact, a large part of what we think of as economic activity is designed to accomplish what high transaction costs would otherwise prevent or to reduce transaction costs so that individuals can negotiate freely and we can take advantage of that diffused knowledge of which Friedrich Hayek has told us.

The generally accepted view is that markets are always right -- that is, market prices tend to discount future developments accurately even when it is unclear what those developments are. I start with the opposite view. I believe the market prices are always wrong in the sense that they present a biased view of the future.

If you let markets - in general, my belief is that if you let markets give you information, they'll give you the information rather than artificially prop up everything.

It is a law of nature that everything run by the government will get more expensive and worse over time. Everything run by the private sector will get better and cheaper over time. The fact that [Obamacare] starts this badly does not bode well....We want healthcare run on the same system that gave us cell phones, flat screens, Jerry Garcia chia pets. Everything you submit to the free market...keeps getting better and better.

Unfortunately, skill in evaluating the business prospects of a firm is not sufficient for successful stock trading, where the key question is whether the information about the firm is already incorporated in the price of the stock. Traders apparently lackthe skill to answer this crucial question, but they appear to be ignorant of their ignorance.

The efficient market theory is one of the better models in the sense that it can be taken as true for every purpose I can think of. For investment purposes, there are very few investors that shouldn't behave as if markets are totally efficient.