Is GPT-5 really worse than GPT-4o? Ars puts them to the test. It's OpenAI vs. OpenAI on everything from video game strategy to landing a 737.

Learn how two-tailed tests determine statistical significance in hypothesis testing by evaluating if a sample differs from a population mean. Discover real-world applications.

Analysis of variance (ANOVA) is a statistical analysis tool that separates total variability found within a data set into two components: random and systematic factors.