Category Archives: Miscellaneous

The Nash Bargaining Example

While I was doing some research on machine learning, I unexpectedly came across an old economics problem that I hadn’t seen in a long time — the Nash Bargaining Problem. Suppose Bill and Jack have some items. Each item has … Continue reading

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Experimental Fighter Planes During World War II

I’ve always been interested in history from all eras. War is awful but war often leads to fast technological advances. Here are some experimental U.S. fighter planes that were built during World war II (1940 – 1945). None of these … Continue reading

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Explaining protobuf And Why I Don’t Use It Very Often

Protocol Buffer, also known as protobuf, is an interesting alternative to XML or JSON or C-family language classes or structs. Briefly, you can define what is very much like a class using a special (but very simple) language. Then you … Continue reading

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The Gale-Shapley Algorithm for the Stable Marriage Problem

Suppose there are 4 men and 4 women. Each man and each woman has an internal mental list of who their preferred mate would be. You want to match the men and women in marriage so that the marriages are … Continue reading

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Statistics and the Murder of Erik Tornblom

I read a news story about the use of statistics in the criminal justice system. The case involved the murder of Erik Tornblom by a man named Marcus Robinson. Erik was 17-year old high school student who worked at a … Continue reading

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Example of the Tortoise and Hare Algorithm

The tortoise and hare algorithm is a technique to determine if a linked list is circular or not. Briefly, if you set two pointers, p and q, to the start of a linked list, and then iterate by advancing p … Continue reading

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The Chinese Restaurant Process

The Chinese Restaurant Process is very simple and best explained by example. Suppose there is a Chinese restaurant that has 4 tables. There are currently 7 customers: 4 customers at table #1, 2 customers at table #2, 1 customer at … Continue reading

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Quantum Circuits

I’ve been reading about quantum computing for many years. I’m a pretty smart guy, but I have extreme difficulty grasping quantum. There are several issues, not the least of which is that quantum is extremely deep and difficult. Anyway, I … Continue reading

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The Discrete Logarithm Problem

The discrete logarithm problem is used in cryptography. Given values for a, b, and n (where n is a prime number), the function x = (a^b) mod n is easy to compute. For example, if a = 3, b = … Continue reading

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Computing a Stirling Number of the Second Kind from Scratch Using Python

A “Stirling number of the second kind” — S(n, k) — is the number of ways to partition n items into k subsets. For example, the number of ways to group n=4 items into k=2 subsets is 7. Suppose the … Continue reading

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