mc-stan.org

If you're new to Ahrefs and want to run your first SEO audit, the fastest path is: open Site Explorer, enter your target URL, review the Overview for a health snapshot, then dig into Organic Keywords, Top Pages, and Site Audit to find specific problems. From there, build a short prioritized to-do list instead of trying to fix everything at once.

This tutorial walks through that workflow using a realistic starting scenario, explains what the numbers mean, and shows how to turn findings into actions.

Before You Start: Pick a Narrow Scope

A common beginner mistake is auditing an entire large website on day one. The reports become overwhelming, and you can't tell which issues matter.

Instead, choose one of these starting points:

• A single important page (your homepage or a key product/service page)
• A small site (under ~50 pages, e.g., a personal blog or small business site)
• One section of a bigger site (e.g., /blog/)

For this tutorial, assume you're auditing a small business site with about 30 pages. The same steps scale up later.

You'll need an Ahrefs account to follow along. Ahrefs offers paid plans, and pricing and feature limits change over time, so check the current Pricing page for what's included in each tier before committing.

Step 1: Enter Your Target in Site Explorer

Site Explorer is Ahrefs' core tool for analyzing any website or URL.

1. Open Site Explorer from the top navigation.
2. In the search box, paste your domain (e.g., example.com).
3. Choose the Exact URL or Domain mode depending on scope. For a full-site view, use Domain or Prefix; for a single page, use Exact URL.
4. Press Enter.

You'll land on the Overview report. Don't try to absorb everything — focus on four numbers first.

Reading the Overview Snapshot

Important caveat: Ahrefs' traffic and keyword numbers are estimates based on its own data. They won't match Google Search Console or your analytics exactly. Treat them as directional, not absolute.

Step 2: See What You Already Rank For

Go to Organic Keywords in the left sidebar. This shows queries where your site appears in search results.

Sort by Traffic (descending) to see which pages bring the most estimated visitors. Then look for:

• Keywords ranking in positions 4–15 — these are often the easiest wins. A small content or on-page improvement can push them onto page one.
• Keywords with high volume but low position — potential opportunities if the topic is relevant.
• Irrelevant keywords — if you rank for something off-topic, it may signal thin or mismatched content.

Write down 5–10 of the position 4–15 keywords. These become your first optimization targets.

Step 3: Find Your Best and Weakest Pages

Open Top Pages. This ranks your URLs by estimated organic traffic.

Look for two things:

1. Your top performers — understand what topics and formats work. Can you create more content like this?
2. Pages with traffic but poor rankings — these may need on-page fixes (title, headings, internal links).

If a page gets zero traffic and targets a topic you care about, it's a candidate for a rewrite or consolidation.

Step 4: Run a Technical Site Audit

Now move to Site Audit. This crawls your site and flags technical and on-page issues.

1. Click Site Audit → New project.
2. Enter your domain and set crawl settings (default is usually fine for a small site).
3. Start the crawl and wait for it to finish.

Once complete, you'll see a Health Score and a list of issues grouped by category.

Which Issues to Fix First

Not all issues are equal. Prioritize in this order:

Ignore low-impact warnings (like minor meta description length) until the big items are handled.

Step 5: Turn Findings Into a To-Do List

You now have raw data. Convert it into a short, actionable list. Example:

1. Fix 3 broken links found in Site Audit.
2. Rewrite title tags on 5 pages with duplicate titles.
3. Improve 4 pages ranking in positions 6–12 by adding missing subtopics and internal links.
4. Remove or update 2 thin pages with no traffic.

Keep the list to 5–10 items max for your first audit. Finishing a short list beats starting a long one.

Common Beginner Mistakes

• Chasing every red flag. Site Audit flags many minor issues. Fix what affects rankings and users first.
• Trusting estimates as exact numbers. Ahrefs data is modeled, not measured from your analytics.
• Auditing a huge site too early. Start small to learn the interface.
• Ignoring search intent. A page can be technically perfect but still fail if it doesn't match what searchers want.
• Forgetting to re-crawl. After fixes, run Site Audit again to confirm improvements.

Where to Go Next

Once your first audit is done:

• Compare with competitors using Site Explorer's Competing Domains and Content Gap reports.
• Track keyword rankings over time with Rank Tracker.
• Explore backlink opportunities in the Backlinks and Link Intersect reports.
• Set up recurring Site Audit crawls so new issues surface automatically.

Your first audit isn't about perfection — it's about building a repeatable habit: enter a target, read the key reports, pick the highest-impact fixes, and act. Do that once a month and your site's health compounds.

Working with data means turning raw records into understanding. In practice, that breaks into five repeatable activities: collecting data, cleaning it, exploring it, visualizing it, and interpreting what the results do and do not support. Data visualization and statistics are two halves of the same job — statistics tells you whether a pattern is real and how uncertain it is, while visualization shows you the shape of the pattern and communicates it to others. You do not need a math or programming background to start; you need a question, a small dataset, and a tool simple enough that you spend your time thinking about the data rather than the software.

The Five Core Activities of Data Work

Most data projects, from a personal budget spreadsheet to a public health dashboard, move through the same stages.

1. Collecting

You gather observations: survey responses, website logs, sensor readings, government tables, or a hand-built spreadsheet. The key decision here is what counts as one row (a person? a day? a transaction?) and what each column measures. Getting this "unit of observation" wrong causes problems that no amount of later analysis can fix.

2. Cleaning

Real data arrives messy. Cleaning means handling missing values, fixing inconsistent categories ("USA," "U.S.," "United States"), correcting types (a date stored as text), and removing duplicates. Beginners are often surprised that this is the most time-consuming step. It usually is.

3. Exploring

Before making charts for others, you look for yourself. What is the range of each variable? Are there outliers? How are two variables related? Simple summaries — counts, averages, minimums, maximums — and quick scatterplots answer most early questions.

4. Visualizing

You encode values as position, length, color, or size so that patterns become visible. A good chart answers one question clearly. A bad chart hides the answer behind decoration or distorts it through a misleading axis.

5. Interpreting

You decide what the pattern means, how confident you should be, and what alternative explanations exist. This is where statistics and careful reasoning matter most.

Visualization vs. Statistics: How They Complement Each Other

These are not competing approaches. They answer different questions about the same data.

A practical rule: visualize to discover, model to confirm, visualize again to communicate. A scatterplot might reveal that one region behaves completely differently from the rest; a statistical model then tests whether that difference holds up; a final chart shows the finding to an audience.

Beginner-Friendly Tools and Formats

You can start with tools you already have.

• Spreadsheets (Excel, Google Sheets): Best for datasets under a few thousand rows. Built-in chart types cover bar, line, scatter, and pie. Learn to sort, filter, and use pivot tables.
• Chart types to master first: bar charts for comparisons, line charts for change over time, scatterplots for relationships, and histograms for distributions. These four cover most everyday questions.
• Simple code options: If you want to go further, R (with ggplot2) and Python (with matplotlib or plotly) are common. Both have large free learning communities. Start with one, not both.
• Design principles that matter more than the tool: label your axes, start bar charts at zero, avoid 3D effects, use color to encode meaning rather than decoration, and put the most important comparison in the most prominent position.

A Realistic Starting Path

If you have no data background, this sequence works:

1. Pick a question you actually care about. "How has my city's rent changed over ten years?" beats a generic tutorial dataset.
2. Find a small, public dataset. Government open-data portals and statistical agencies publish free tables.
3. Load it into a spreadsheet and clean it. Fix types, remove duplicates, note missing values.
4. Make three charts. One bar, one line, one scatter. Write one sentence under each describing what you see.
5. Ask what could be misleading. Is the sample representative? Is the time range fair? Could a third factor explain the pattern?
6. Repeat with a slightly harder question. Add a second variable, or try a simple statistical summary like a correlation or a group comparison.

Expect the first project to take longer than you think, mostly in cleaning. That is normal, not a sign you are doing it wrong.

What Data Can and Cannot Answer

Data can describe what happened, compare groups, estimate relationships, and quantify uncertainty. It cannot, on its own, establish causation without a proper study design, tell you what you should value, or compensate for a biased sample. A dataset collected from volunteers will not represent the general population no matter how sophisticated the analysis. Treat every result as "what this data suggests under these conditions," not as a final verdict.

Where to Go Next

FlowingData (flowingdata.com) focuses on data visualization and statistics for people who want practical, well-designed charts rather than academic theory. It is a reasonable place to browse examples, see how real datasets are turned into clear graphics, and pick up habits you can apply in your own work. Pair it with one spreadsheet tutorial and one public dataset, and you have everything you need for a first project.

The short version: working with data is a craft of asking clear questions, cleaning messy inputs, looking before you model, and communicating honestly. Start small, start visual, and let the statistics grow as your questions get harder.

Stan is a probabilistic programming language for Bayesian data analysis. It handles models where you specify a probability distribution over parameters and data, then estimate the posterior distribution through sampling or optimization. The practical range runs from simple linear regression to multi-level (hierarchical) models and time-series analysis, and it is designed for complex data scenarios where interpretable results matter.

The core mechanism: Bayesian inference via probabilistic programming

Instead of fitting a model with a fixed formula and returning point estimates, you write a Stan program with three main blocks:

• data — declares the inputs, their types, and any bounds.
• parameters — declares the unknowns to be estimated.
• model — states the prior and the likelihood.

Stan then draws from the posterior. The excerpt on mc-stan.org shows a minimal Bernoulli example:

data {
  int<lower=0> N;
  array[N] int<lower=0, upper=1> y;
}
parameters {
  real<lower=0, upper=1> theta;
}
model {
  // uniform prior on interval 0,1
  theta ~ beta(1, 1);
  y ~ bernoulli(theta);
}

Reading it: N is the number of observations, y is a binary outcome, theta is the unknown success probability, the prior is beta(1,1), and the likelihood is Bernoulli. The output is a posterior distribution for theta, not a single number — which is what makes the results interpretable in terms of uncertainty.

Model families Stan is built for

The site describes the language as suitable for "a wide range of applications, from simple linear regression to multi-level models and time-series analysis." In practice that covers:

The key constraint is not the model family but the ability to write the joint distribution. If you can express your assumptions as a prior and a likelihood, Stan can estimate it.

Interfaces and where it runs

Stan is a multi-language, cross-platform toolkit. The site lists interfaces for Python, Julia, R, and the Unix shell, so you can stay in your existing programming environment. It runs on laptops, clusters, or in the cloud.

A "rich ecosystem of tools for validation and visualization" supports checking that a model behaved correctly and communicating the results — relevant when the goal is decision-making rather than just a fitted number.

When Stan is a good fit — and when it is not

Choose Stan when:

• You need a full posterior distribution, not just a point estimate.
• Your model is hierarchical, temporal, or otherwise not covered by standard regression software.
• You want to state priors explicitly and check them.
• You work in R, Python, Julia, or a shell environment and want to stay there.

Look elsewhere when:

• A closed-form or frequentist solution already answers your question.
• You cannot write the model as a prior plus a likelihood.
• You need results but have no way to validate the sampler's output.

Getting started and getting help

The site points to several entry points:

• Documentation, tutorials, and case studies for learning Stan on your own projects.
• The Stan forums, which support all user levels — from installing software, to writing Stan programs, to advanced Bayesian modeling and methodology.
• The Prior Choice Recommendations wiki page for guidance on appropriate priors.
• Developer resources: the Stan Developer Wiki, the Developers category on the forums, and the Slack channel mc-stan.slack.com for informal developer discussions.

A reasonable first path: install an interface for the language you already use, run the Bernoulli example above, then move to a case study close to your own data structure before writing a model from scratch.

An open-source UI element library is a collection of individual, ready-made interface pieces—buttons, cards, inputs, toggles, loaders—that you copy into your own project and adapt. A UI framework, by contrast, is a structured system of components, conventions, and often a theming layer that governs how your whole interface is built. The practical difference: an element library gives you a snippet; a framework gives you a way of working. If you need a polished button in ten minutes, reach for the element library. If you're building a 40-screen product with a team, you probably want the framework.

What "open-source UI element library" actually means

The term gets used loosely, so it helps to separate the parts:

• Open-source: the code is publicly available, and the license tells you what you may do with it—copy, modify, redistribute, or use commercially.
• UI element: a single, self-contained piece of interface, usually small enough to read in one sitting. A button with hover states, a pricing card, a search field.
• Library: a browsable, searchable collection of those elements, typically contributed by many different people.

On a site like Uiverse, elements are shared by a community and written in plain CSS or Tailwind. You find one you like, copy the markup and styles, paste them into your project, and adjust colors, spacing, and text to fit. There's no package to install and no build step required—which is exactly the appeal, and also the source of most of the confusion.

Element library vs. UI framework: the core differences

The table isn't a verdict. It's a map of trade-offs. Element libraries win on speed and freedom; frameworks win on consistency and maintenance.

Licensing and attribution: what to check before you paste

This is where people get into trouble, and it's worth slowing down for.

1. Find the license. Every element or collection should state one. Common open-source licenses include MIT, Apache-2.0, and BSD. Some projects use copyleft licenses like GPL, which can impose obligations if you redistribute your code.
2. Understand what the license permits. MIT and Apache-2.0 are permissive: you can typically use the code in commercial and closed-source projects. Copyleft licenses may require you to release derivative source under the same terms.
3. Check attribution requirements. Permissive licenses usually require you to keep the copyright notice and license text somewhere in your project. That's a real obligation, not a formality.
4. Look for per-element terms. On community sites, the site's overall terms and the individual contributor's stated wishes may differ. If a contributor asks for credit, honor it.
5. When in doubt, ask or avoid. If a snippet has no license at all, you don't have clear permission to reuse it. Treat "no license" as "not open source," even if the code is publicly visible.

This article is general information, not legal advice. For commercial products with real exposure, have someone qualified review the licenses you're relying on.

How to use a community element in your project: a practical workflow

Here's a repeatable process that avoids most of the usual mess.

1. Start from a real need, not a browsing session

Decide what you need first—"a compact primary button with a loading state"—then search. Browsing aimlessly produces a pile of pretty snippets that don't fit together.

2. Copy the smallest version that works

Take the markup and the styles. Strip anything you don't need: demo wrappers, extra animations, decorative layers. Less code means fewer surprises.

3. Convert it to your conventions

If your project uses design tokens or CSS variables, replace hard-coded values:

/* Before: hard-coded */
.button { background: #4f46e5; border-radius: 8px; }

/* After: token-based */
.button { background: var(--color-primary); border-radius: var(--radius-md); }

This one step is what keeps a copied element from looking like a foreign object in your UI.

4. Check accessibility before you ship

Community elements vary widely here. Verify at minimum:

• Keyboard focus is visible and the element is reachable by Tab.
• Color contrast meets WCAG AA (4.5:1 for normal text).
• Interactive elements use semantic HTML (<button>, not a clickable <div>).
• Form inputs have associated labels.
• Motion respects prefers-reduced-motion.

5. Test in context

Paste it into a real page with real content. Long labels, small screens, and dark mode break more copied elements than anything else.

6. Note where it came from

Keep a short comment or an internal credits file: source, license, date. Future you—and your legal reviewer—will be grateful.

Where element libraries genuinely shine

• Prototypes and demos: you need something clickable today, not a design system.
• Landing pages and marketing sites: a handful of distinctive elements, each custom.
• Filling gaps: your framework lacks one specific component, and you don't want to build it from scratch.
• Learning: reading well-made CSS is one of the fastest ways to improve.
• Small projects: a personal site doesn't need a theming architecture.

Where they fall short

• Consistency at scale: ten elements from ten contributors rarely look like one product.
• Maintenance: you own every copy. When your design changes, you edit each one.
• Accessibility debt: you inherit whatever the contributor did or didn't do.
• No upstream fixes: a bug fixed in the original won't reach your copy.
• Integration friction: different naming conventions, different units, different assumptions about resets.

When to choose which

Choose an element library when the scope is small, the timeline is short, or you need a few distinctive pieces rather than a whole system.

Choose a framework or design system when multiple people build multiple screens over months, when consistency is a product requirement, or when accessibility and theming need to be guaranteed rather than checked.

A hybrid works well for many teams: adopt a framework for the structural components—forms, navigation, layout—and borrow individual elements for the places where you want personality. Just route every borrowed element through the same token and accessibility checks, so it lands as part of your system rather than beside it.

The short version: open-source UI element libraries are a fast, flexible way to get good-looking interface pieces into a project. They are not a substitute for a design system, and the license and accessibility details are the part worth reading carefully.

Stan is an open-source software platform for Bayesian data analysis. It provides a probabilistic programming language for building statistical models and performing Bayesian inference, with interfaces for Python, Julia, R, and the Unix shell. It is the right tool to look at if you want to fit Bayesian models — from simple linear regression to multi-level and time-series models — and prefer to write the model declaratively rather than hand-code a sampler.

What Stan actually does

Stan separates the model from the computation. You write a model in the Stan language, and Stan handles the inference. The site describes this as combining "powerful statistical modeling capabilities with user-friendly interfaces."

The core pieces:

• A probabilistic programming language. You declare data, parameters, and a model; Stan compiles it and runs the inference.
• Bayesian inference. The site frames the goal as "more accurate and interpretable results in complex data scenarios."
• Flexible and scalable. The same language covers simple linear regression through multi-level models and time-series analysis, and runs on laptops, clusters, or in the cloud.
• A toolkit around the model. Validation and visualization tools support "decision-making and communication."

A concrete example

The site's own example is a Bernoulli model — estimating a probability theta from binary outcomes:

data {
  int<lower=0> N;
  array[N] int<lower=0, upper=1> y;
}
parameters {
  real<lower=0, upper=1> theta;
}
model {
  // uniform prior on interval 0,1
  theta ~ beta(1, 1);
  y ~ bernoulli(theta);
}

Read it as three blocks: data is what you supply, parameters is what Stan estimates, and model states the prior and the likelihood. You don't write a sampler — declaring y ~ bernoulli(theta) is enough for Stan to infer the posterior for theta.

Interfaces and where it runs

The same models run across these environments, on laptops, clusters, or in the cloud — so you can prototype locally and scale up without rewriting the model.

Learning resources on the site

• Getting Started and Documentation — installation and language reference.
• Tutorials and Case Studies — worked examples you can adapt to your own projects.
• Learning Resources and Domain-specific Publications — material organized by field.
• Diagnostics and Warnings — how to tell when a fit has gone wrong.
• StanCon Talks — conference presentations.
• Prior Choice Recommendations wiki — guidance on choosing priors for use with Stan.

Community and developer support

The Stan forums cover "all user levels and topics, from installing software, to writing Stan programs, to advanced Bayesian modeling techniques and methodology." For development work there is the Stan Developer Wiki, a Developers category on the forums, and the Slack channel at mc-stan.slack.com for informal developer discussion.

When Stan is a good fit

Choose Stan when your problem is genuinely Bayesian, when you need a model that doesn't fit a standard canned procedure (multi-level structure, custom likelihoods, time series), or when you want the same model to run from R, Python, Julia, or the shell. If you only need a quick frequentist regression with no custom structure, a lighter library in your existing language may get you there faster — Stan's value shows up when the model itself is the hard part.