# Is probability theory useful in electrical engineering [closed]

I have a few days off after finishing this semester and I am hoping to study something. Ideally, I would like to be able to benefit from it in any upcoming courses I might take. I'm thinking of either Fourier Series or Probability Theory. Currently I'm leaning towards Fourier because it's essential to Electrical Engineering, however Probability Theory seems intriguing (also opens up interesting areas such as Machine Learning).

So how relevant is Probability Theory to an undergraduate Electrical Engineering student?

• For all answerers, it's probably a good idea to read the Stack Exchange guidelines on subjective questions (and their answers) before answering. Nov 9, 2014 at 23:49

Both Fourier and Probabilities are extremely useful and relevant to Electrical Engineering, so there is no doubt that you will need both any way.

As you are asking specifically about the relevance of Probability Theory I am going to talk only about it, but as I have already mentioned there can't be a comparison between them as you are certainly going to need both of them, one more that the other depending on what area of Electrical Engineering you decide to focus on. One can write countless lines about where you can use probabilities but I am writing the first things that come to mind.

Probability Theory is one one the most important courses in Electrical Engineering. In most Universities you are taught an Introduction to Probability Theory and Statistics and then in other classes you are learning about more specific areas depending on the needs of each class.

For instance if you are going to choose

1. Control Systems
2. Signals
3. Information Theory
4. Communications

then you are certainly going to need probabilities in most of your classes. But that is not the case if you are going to choose Energy or Motors.

(The areas I refer to are just examples and there are a lot more, both in the list that needs probabilities and also in the one that doesn't.)

• It is funny because when you actually go off and work in the power industry, there tends to be a lot of probabilistic analysis such as LOLP, LOLE and you also have to analyze energy stocks such as MCP which is a stochastic process and not to mention monte carlo simulations Jan 6, 2015 at 5:48
• @IllegalImmigrant probabilities are everywhere nowadays so I only mention where there is a heavy use of them and where the OP is going to use them most. Also the OP mentions if he is going to need them for his study, so the answer is that in Energy classes mostly he is not going to need them. But as you say when you have to work in a field a lot of things are very different than in the class. :)
Jan 11, 2015 at 11:53

Probability theory is very relevant to Electrical Engineering -- in fact several universities have courses just on this topic, such as University of Utah's ECE 3530/CS 3130 - Engineering Probability and Statistics and USC's EE503 Probability for Electrical and Computer Engineers. Take a look at the syllabi for these courses and you will get a feel for the many different topics covered.

Probability is particularly relevant in the area of quality engineering, and being able to design reliable circuits where you have to take into account the tolerance of various components, and the predicted lifetimes. What is the mean-time-to-failure (MTTF) of your system?

Where can you get by with a 20% tolerance capacitor instead of a more expensive 5% one? In a recent design of mine, I had to use a 0.1% resistor in a current sensor instead of the usual 1% resistors I always use.

I have used a Poisson distribution to predict the maximum amount of memory needed so I would have adequate buffers to handle peak incoming traffic in an embedded system based on the expected average traffic entering the system.

Communications theory and error correction are all about probability and statistics, where the maximum amount of information is jammed into the smallest amount of bandwidth, while dealing with possibly very noisy channels.

You are already considering the most relevant topic. If you are considering looking into probability theory it is useful in Engineering in general

The most relevant part is FMEA - Failure Mode and Effects Analysis where the failure of a functional part is determined & then the end effect at system level.

Another aspect is on complete circuit analysis. Its all well and good to design (for argument sake) a voltage divider, but in practice it is never just a 10k:10k...

Those 10k themselves have tolerance, drift with life, temperature variance. Then there are the other aspects of such a circuit. The variability of the PSU, the range of the ADC it might be hooked up to.

Probability theory is directly related to FMEA while a healthy knowledge of probability will help with circuit analysis

Given a few days off between EE undergraduate terms, should you study Fourier series or probability theory? I would prioritize probability theory ahead of Fourier analysis, especially for reasons well stated by Adam. Both subjects are quite valuable for a well rounded EE. My MSEE focus was communications theory, which relies on both.

Only you can provide the best answer for yourself. My general advice to engineering undergraduates is to get a head start before each new class meets, for example by reading every textbook preface and chapter 1 ahead of class. Most students are unable to absorb all the material presented; preparation gives an edge.

Best wishes for you.

• Welcome to EE.SE. This is not a discussion forum. You should only answer if you have something new to add that directly answers the question being asked. If you want to support a previous answer, the best way is by voting it up, which you'll be able to do after gaining a small amount of reputation through submitting questions and answers. Nov 9, 2014 at 23:29
• @ThePhoton This whole thread is opinion-based. I'm surprised that it hasn't been closed yet (and migrated to Academia.SE, possibly). In light of that, L Jones' is not a particularly malignant post. In fact, I'd second his advice about reading-up during the break. Nov 9, 2014 at 23:36
• @NickAlexeev, I agree the question is at least on the edge of opinion based. But I do think it is possible to generate useful answers that address the core question: How is probability used in EE?. Because the question leans towards opinion-based, it's even more important to stick to answers that address the question directly. Nov 9, 2014 at 23:46

To detect the informantion received is correctly, depends on signal per noise ratio based on probability only