Author: Will
Tables of Poisson Cumulative Distribution
The following tables provide the Cumulative Distribution Function (CDF) for a Poisson random variable \( X \). For a given mean = \( \lambda \), each cell represents the probability that the number of events \( X \) is less...
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Python Code to Simulate Two Categorical Independent Variables for Linear Regression
This following python code generates a simulated data, which includes two categorical independent variables and one continuous variable. This simulated dataset can be used for linear regression or ANOVA. import pandas as pdimport numpy as np# Set seed for consistencynp.random.seed(42)#...
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How to Interpret the Interaction Between Two Continuous Variables
This tutorial is about how to interpret the interaction between two continuous independent variables in a regression model. In this example, the dependent variable is Mileage per gallon (MPG), and the independent variables are car weight (WT), horsepower (HP) and...
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Select Cases in SPSS
In this tutorial, we will explore how to select cases in SPSS. Based on the selected cases, this tutorial will show you how to analyze data after applying those filters. This process allows you to focus on specific groups within...
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SPSS Tutorial for Beginners: Data vs. Variable Views and Descriptive Statistics
This tutorial provides an introduction to using SPSS for basic data analysis. You will learn how to navigate the SPSS interface and perform simple descriptive analyses using an example dataset. The goal is to help beginners become familiar with key...
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Boxplot Analysis
Boxplot analysis can visually summarize data’s spread, symmetry, and outliers. 1. Key Terms to Know Interquartile Range (IQR): IQR = Q3 – Q1. This is the “box” itself. It represents the middle 50% of the data. Outliers: Data points that...
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Save or Move Your WordPress Website
You might want to transfer your website to another hosting provider. After spending 2 days trying to figure it out, I feel it would be not a bad idea to write it down here for 2 purposes: (1) For my...
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Principal Component Analysis
Start with your data matrix \(X =\begin{bmatrix}2 & 0 \\0 & 2 \\3 & 3 \\\end{bmatrix} \) Step 1: Centering (standard for PCA): \( X_{centered} =X – \bar{X} \) Sometimes you also scale (normalize) each feature to have unit variance...
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Z-Score: Definition, Formula, and Example
1. Definition A Z-score, also known as a standard score, measures how many standard deviations a data point is from the mean of a dataset. It is used in statistics to standardize data, compare different distributions, and detect outliers. A...
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Chi-Square Critical Value Table
Chi-Square Critical Value Table (Distribution Table) df p = 0.995 p = 0.99 p = 0.975 p = 0.95 p = 0.9 p = 0.75 p = 0.5 p = 0.25 p = 0.1 p = 0.05 p = 0.025...
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