hypothesis

3 easy ways to compare the mean value of a sample with other, expected valuesPhoto by Edge2Edge Media on UnsplashData scientists and analysts often have to work with mean values and need to compare the mean value of a sample with a known expected value or the mean value of another sample. Statistics helps us with a powerful set of hypothesis tests we can perform for such tasks.Let’s say that we measure something like the height of Mount Everest. We know that it’s 8848 meters. After we measure it, we get 8840 meters with a…

A refresher on how to interpret statistical inference correctlyPhoto by Scott Graham on UnsplashStatistical inference, such as hypothesis testing and confidence interval, are well-known concepts in statistics. However, many people including myself would sometimes misinterpret the result from statistical inference. Hopefully, this article would serve as a refresher on how to interpret statistical inference correctly.What is Statistical Inference?If we are studying the average household income in Los Angeles, it is…

Create Clean and Robust Tests with Property-Based TestingImage by AuthorImagine you are trying to figure out whether the function processing_fn is working properly. You use pytest to test the function with an example.The test passed, but you know that one example is not enough. You need to test the function with more examples to make sure that the function is working properly with any data.To do that, you might use pytest parameterize, but it is difficult to come up with every example that might result in failures.Even if…

Hearing loss can reduce your opportunities, cause social withdrawal, and result in emotional problems. A new hypothesis about crocodile ears.Over 1.2 billion individuals worldwide have hearing loss. Crocodiles, on the other hand, have excellent hearing for their whole lives and can live up to 70 years. One reason is that crocodiles can create new hair cells, and an Uppsala University research team is currently investigating why. Hopefully, understanding crocodile biology can benefit those who have hearing loss.Light…

For data scientists and analysts in businessPhoto by Tingey Injury Law Firm on UnsplashThere is only a one in a million chance that the accused would match the DNA found at the crime scene. So the accused is guilty beyond reasonable doubt. Sound ok? It isn’t!Based on this evidence alone, the accused may have a good chance of being innocent and this is the logical trap described by the unintuitive but wonderfully illuminating Prosecutor’s Fallacy.When we understand this, we start to see it everywhere in advertising, the…

Understand the concept and find how to avoid typical mistakesPhoto by Andrew George on UnsplashStudent’s t-tests are commonly used in inferential statistics for testing a hypothesis on the basis of a difference between sample means. However, people often misinterpret the results of t-tests, which leads to false research findings and a lack of reproducibility of studies. This problem exists not only among students. Even instructors and “serious” researchers fall into the same trap. To prove my words, I can link this…

How winning tickets were discovered, debunked, and re-discovered(created by author)The Lottery Ticket Hypothesis (LTH) is related to neural network pruning and can be concisely summarized via the following statement :“dense, randomly-initialized, feed-forward networks contain subnetworks (winning tickets) that — when trained in isolation — reach test accuracy comparable to the original network in a similar number of iterations.”Though a bit difficult to interpret, such a statement reveals that if we:Train a neural network…

Humans take a lot of pride in their brains. We like to think we are an intelligent species, and even though size isn't everything, our noggins are some of the largest nature has to offer.  The idea that our brains are shrinking is not one we like to consider. For more than four decades, experts have mostly ignored the hypothesis put forward time and time again by a close-knit group of paleontologists.Now, the brain shrinkage hypothesis is being put to the test once more, with a team from the University of Nevada, Las…

For millions of people around the world, salvation from long periods of dark thoughts and oppressive feelings comes in pill form, with each dose doing its bit to ensure the balance of a humble neurotransmitter called serotonin remains relatively in check.  In spite of their popularity as a treatment for mood disorders, much of the mechanisms behind antidepressant pharmaceuticals are a complete black box. We can only guess at how they work in treating low moods.More shocking still, those guesses could be completely wrong,…

StatisticsWhat is homoscedasticity again?Photo by Edward Howell on UnsplashI find myself coming back to the basics to refresh my statistical knowledge over and over again. Most people’s first introduction to statistics begins by learning hypothesis testing, which is followed soon after by t-tests and linear regression. This article is a refresher of how to use linear regression for hypothesis testing along with the assumptions that have to be satisfied in order to trust the results of your linear regression statistical…