Skip to content
datarekha
Blog Production AI · GATE DA · how concepts actually work · Page 3 of 13

From theory to the systems that demand real understanding.

Long-form pieces on how production-AI teams orchestrate agents, serve models, and build the stack, plus GATE DA essays that turn probability, linear algebra, DBMS, ML, and AI into durable concepts.

295 posts · 20 categories
Visualization Jun 10, 2026

Your t-SNE plot is lying to you (three ways)

t-SNE and UMAP reveal clusters PCA hides — but cluster sizes, the gaps between clusters, and even the shapes are often artifacts. How to read these plots without fooling yourself, and when to reach for UMAP instead.

9 min read Read
Infrastructure Jun 8, 2026

For some AI deployments, deliverable electricity is becoming a binding co-constraint

For some AI deployments, deliverable electricity is becoming a binding co-constraint. Why data-center power matters, and how inference makes every AI query an energy cost.

9 min read Read
LLMs Jun 8, 2026

Attention is O(n²) — and Mamba's linear escape

Attention costs O(n²), so long context gets expensive fast. State-space models like Mamba do linear sequence work at fixed dimensions, which can make some very long streaming workloads more tractable. Some long-context workloads may favor hybrid designs, but quality, latency, memory, and cost must be measured.

11 min read Read
LLMs Jun 8, 2026

Beyond next-token: world models and the next paradigm

World models predict the next state of an environment, not merely the next token. See how action-conditioned prediction supports planning, and where visual and latent approaches fail.

10 min read Read
LLMs Jun 8, 2026

Diffusion language models: when AI writes text all at once

Masked discrete diffusion language models often start from a masked sequence and refine many positions in parallel over several sequential denoising passes.

13 min read Read
LLMs Jun 8, 2026

Reading a model's mind: sparse autoencoders explained

Sparse autoencoders pull human-readable features out of an LLM's tangled activations — the breakthrough tool of mechanistic interpretability.

10 min read Read
LLMs Jun 8, 2026

How reasoning distillation gives small models stronger math and code behavior locally

A practical guide to teacher signals, verified reasoning traces, supervised fine-tuning, evaluation, and serving small reasoning models on local hardware.

10 min read Read
LLMs Jun 8, 2026

DPO vs PPO-based RLHF: when offline preference tuning wins

RLHF aligned chat models with a reward model and a fragile RL loop. DPO drops both, learning the same preferences directly from chosen-vs-rejected pairs.

11 min read Read
LLMs Jun 8, 2026

Small models for narrow tasks: when they beat larger models

When a small language model can match or outperform a larger one on a stable, measurable task slice—and when that claim fails.

11 min read Read
LLMs Jun 8, 2026

Why a deployed model does not learn from a chat—and how fine-tuning can cause forgetting

A deployed checkpoint normally does not update its weights from a conversation unless an explicit memory or update loop exists. Fine-tuning on sequential data can cause catastrophic forgetting, meaning degraded old-task performance, but does not necessarily do so. Why continual learning remains an open problem in 2026.

10 min read Read
LLMs Jun 8, 2026

Test-time compute: why thinking longer beats thinking bigger

Test-time compute lets a model think before answering, so a small reasoning model can beat a far larger one. How inference-time scaling works.

10 min read Read
Business Analytics Jun 7, 2026

A/B testing in practice: sample size, p-values, and the traps

A/B testing done wrong wastes months of effort. Master p-values, sample size, and the six traps — peeking, SRM, and more — before your next experiment.

13 min read Read
Business Analytics Jun 7, 2026

Cohort analysis: how to actually read a retention curve

Cohort analysis reveals what aggregate retention metrics hide — learn to build a cohort table, read a retention curve, and spot product-market fit signals.

12 min read Read
Time Series Jun 7, 2026

Evaluating forecasts: MAE, RMSE, MAPE, and honest backtesting

A practical guide to forecast accuracy using MAE RMSE MAPE and MASE, plus rolling-origin backtesting to avoid self-deception in time series.

12 min read Read
CLI Jun 7, 2026

find and xargs: bulk file operations without fear

Master the find command and xargs for safe, efficient bulk file operations: handle spaces in filenames, batch deletes, renames, and parallel processing.

11 min read Read
Time Series Jun 7, 2026

The forecasting baselines that quietly beat fancy models

Why forecasting baselines like the naive forecast and seasonal-naive outperform complex models—and how to pick the right one before you build anything fancy.

11 min read Read
Business Analytics Jun 7, 2026

Funnel analysis: finding exactly where users drop off

Master funnel analysis to pinpoint conversion leaks, prioritize fixes by impact, and turn step-by-step drop-off data into real growth.

11 min read Read
Git Jun 7, 2026

git bisect: find the commit that broke it in log(n) steps

Use git bisect to find the exact commit that introduced a regression or bug with binary search over history — O(log n) instead of O(n).

10 min read Read
Git Jun 7, 2026

Branching strategies that scale: trunk-based vs Git Flow vs GitHub Flow

Compare every major branching strategy: trunk-based development, Git Flow, and GitHub Flow — and know which fits your release cadence.

12 min read Read
Git Jun 7, 2026

Git merge vs rebase: when to use which (without wrecking history)

Git merge vs rebase both integrate branches but produce different histories. Learn when each is right, the golden rule, and how to recover when things go wrong.

12 min read Read
Git Jun 7, 2026

Git's three trees: the mental model that makes Git click

Understand git's working directory, staging area, and HEAD so every git command finally makes sense — no more mystery, no more fear.

11 min read Read
CLI Jun 7, 2026

grep, sed, awk: the text-processing trio worth mastering

grep sed awk command line text processing explained: when to use each tool, real recipes, regex fundamentals, and how pipelines compose all three.

13 min read Read
Business Analytics Jun 7, 2026

LTV and CAC: the unit economics every analyst should model

Master LTV and CAC unit economics: correct formulas, cohort methods, payback periods, and the pitfalls that make most models wrong.

12 min read Read
Business Analytics Jun 7, 2026

North Star metrics: the one number that actually moves a business

What a north star metric is, how to choose one, and why a single well-chosen number beats a dashboard of 40 KPIs.

11 min read Read