← All ArticlesData Science & Applications

Data Science & Applications

Exploratory data analysis, data visualization, A/B testing, and Bayesian statistics — where core statistical methods meet real-world data work.

16 articles

Illustration: Training error keeps falling, but held-out error turns back up: that is overfitting

Sep 29, 20268 min read

Where Statistics Actually Shows Up in Machine Learning

Read article →

Illustration: Rotate to the axes with the most spread: PC1 carries most of the information, PC2 the rest

Sep 24, 20269 min read

Principal Component Analysis (PCA): A Step-by-Step Two-Variable Example

Read article →

Illustration: Survival from time-to-event data; tick marks are censored patients still under observation

Sep 22, 20268 min read

The Kaplan–Meier Survival Curve: Handling Censored Data

Read article →

Illustration: Intervals describe a repeatable procedure; a posterior describes belief about this parameter

Sep 18, 20268 min read

Bayesian vs. Frequentist Statistics: Two Ways of Reasoning About Uncertainty

Read article →

Illustration: Every observation is held out exactly once; the k errors are averaged for an honest estimate

Sep 7, 20267 min read

K-Fold Cross-Validation: Estimating How a Model Performs on New Data

Read article →

Illustration: A point beyond the control limits (circled) signals a special cause, not ordinary variation

Sep 4, 20267 min read

Control Charts: Telling Real Process Shifts From Ordinary Noise

Read article →

Illustration: The vital few: two of seven causes account for 70% of all defects

Sep 2, 20267 min read

Pareto Charts: Finding the Vital Few Causes, With a Worked Example

Read article →

Illustration: Points on the line mean normal; an S-shape like this one means heavier tails than the normal

Sep 1, 20267 min read

Q-Q Plots: Checking Normality by Eye, With a Worked Example

Read article →

Illustration: Counts (tickets per day) modelled with a log link: the mean grows multiplicatively with x

Aug 27, 20267 min read

Poisson Regression: Modeling Count Data From Predictors

Read article →

Illustration: The same 52 vs 55: a truncated axis (left) exaggerates the gap; the honest axis (right) does not

Aug 26, 20267 min read

Data Visualization Principles: Choosing Honest, Effective Charts

Read article →

Illustration: Conversion rates from 5,000 visitors each, with 95% intervals: is B genuinely better than A?

Aug 22, 20268 min read

A/B Testing: The Statistics Behind Product Decisions

Read article →

Illustration: A monthly series split into its parts: the moving average (green) smooths out the seasonal swing

Aug 15, 20268 min read

Time Series Basics: Trend, Seasonality, and Moving Averages

Read article →

Illustration: Distribution, relationship and outliers — three quick views before any formal model

Aug 14, 20267 min read

Exploratory Data Analysis: The Critical First Step in Any Analysis

Read article →

Illustration: Armour where returning planes are hit and you shield the wrong spots: the lost ones tell the story

Aug 7, 20267 min read

Survivorship Bias: What the Missing Data Doesn't Tell You

Read article →

Illustration: Both subgroups trend upward, yet combining them reverses the trend: the group mix matters

Aug 5, 20268 min read

Simpson's Paradox: When Aggregated Data Reverses the Real Trend

Read article →

Illustration: Statistics at work: comparing groups, tracking change, and testing whether a pattern is real

Aug 1, 20269 min read

Statistics in the Real World: Three Full Worked Case Studies

Read article →

Browse other topics

Descriptive Statistics

Mean, median, mode, standard deviation, variance, quartiles and the interquartil…

Probability

Basic probability rules, conditional probability, Bayes' theorem, expected value…

Distributions

The normal distribution, binomial distribution, t-distribution, z-scores, and th…

Sampling & Inference

Sampling distributions, the Central Limit Theorem, standard error and confidence…

Hypothesis Testing

Null and alternative hypotheses, p-values, Type I/II errors, t-tests, chi-square…

Regression & Correlation

Pearson correlation, simple and multiple linear regression, R², and residual ana…

Never miss a Data Science & Applications article

Get new statistics articles, study tips, and platform updates delivered to your inbox every Thursday.