We rarely heard of nonparametric tests while reading standard statistical books. However there are some scenarios where they should be used instead of parametric tests. [1] has beautiful blog about it, I am putting just a summary from that. Different Tests Table below displays various tests, I have verified that all of these tests… Continue reading Parametric and Nonparametric tests

# Category: Statistics

# Hypothesis and T-Distribution

We calculate t-score using hypothesis data We also get degrees of freedom from hypothesis data We supply this value to a function which gives us the probability of hypothesis being true. We can see that t test is a ratio, something like signal to noise ratio. Numerator allows us to center it around zero Denominator… Continue reading Hypothesis and T-Distribution

# Q – Q Plots

Since few days I was coming across to Q-Q plots very often and thought to learn more about it. Many a times we want our data to be normal, this is because we normality is an assumption behind many statistical models. Now how to test normality. Wikipedia has an article about this which lists many… Continue reading Q – Q Plots

# Probability Distribution

We have learned various probability distribution during high school and engineering courses. However at times we forget them, so here I am providing simple practical scenarios for each distribution with no theories involved. Bernoulli Distribution When the random variable has just two outcomes Probability of Drug/Medicine will be approved by government is p = 0.65… Continue reading Probability Distribution

# Interpreting Statistical Values

In the previous post we started exploring statistical domain and will dive in more deeply today. So basically we will try to see what all the values in summary(model) in R suggest. Here is a screenshot of how this summary looks : Significant of Residue? We want our residues to be normally distributed and centered around… Continue reading Interpreting Statistical Values

# Statistical Regression

During my recent flight I got a chance to talk to Samarth, who builds model for quantitative finance. He suggested that behind every machine learning model there are several statistical assumptions and you need to see if your data meets those assumptions. If not you need to make certain transformation. So started to read ISLR… Continue reading Statistical Regression