S2 · Dimensions, metrics and what a report is

Session 2: Dimensions, metrics and what a report is

From hit to report

You've seen individual hits (Session 1). Now let's see how millions of hits become a report.

Aggregation: the magic

A report is aggregated data. Millions of individual hits are grouped and counted.

Example:

Individual hits (raw):

Hit 1: alice, page=home, device=mobile
Hit 2: alice, page=product, device=mobile
Hit 3: bob, page=home, device=desktop
Hit 4: alice, page=home, device=mobile

Aggregated report (what you see in Analysis Workspace):

| Page | Visitors | Mobile | Desktop |
|------|----------|--------|---------|
| Home | 2        | 2      | 0       |
| Product | 1     | 1      | 0       |

The report groups by page (dimension) and counts visitors (metric) by device (another dimension).

Dimensions (what you group by)

A dimension is a category or axis. It answers "break down this data by what?"

Examples:

• Page Name: home, product, checkout
• Device: mobile, desktop, tablet
• Traffic Source: organic, direct, paid, referral
• Campaign: campaign_a, campaign_b, campaign_c
• Form Type: contact, complaint, feedback

In a report, dimensions become rows (or columns in a pivot table).

Metrics (what you count)

A metric is a number you want to count. It answers "how many" or "how much?"

Examples:

• Visitors: unique people (unique ECID)
• Page Views: times a page loaded
• Visits: sessions (groups of hits)
• Revenue: total dollars
• Form Submissions: count of times event5 fired
• Bounce Rate: 1-hit visits / visits

In a report, metrics are the numbers.

Building a report: dimension + metric

Every report is built from one or more dimensions and one or more metrics.

Formula: [Metric] by [Dimension]

Example 1: Simple breakdown

Question: How many page views did each page get?

• Dimension: Page (Home, Product, Checkout)
• Metric: Page Views (10,500, 8,200, 4,800)

Example 2: Multiple dimensions

Question: How many visitors by page and device?

• Dimensions: Page (rows) and Device (columns)
• Metric: Visitors (cell values)

Example 3: Multiple metrics

Question: Visitors and revenue by campaign?

• Dimension: Campaign
• Metrics: Visitors, Revenue

Where dimensions and metrics come from

Automatic (Adobe provides)

• Dimensions: Date, Device, Browser, Referrer, Page Name
• Metrics: Visitors, Visits, Page Views, Bounce Rate, Time Spent

You define with props/eVars

• Props: Hit-level data (e.g., section, page type, search term)
• eVars: Session/visitor-level data (e.g., campaign, customer segment)
• Events: Custom counts (e.g., form submissions, video plays)

Example Super: Report building

Question: How many complaint form submissions by device?

Raw hits:

Hit 1: alice, page=complaint-form, device=mobile, event5 (submit)
Hit 2: bob, page=complaint-form, device=desktop, event5 (submit)
Hit 3: charlie, page=complaint-form, device=mobile, event5 (submit)

Report:

• Dimension: Device (Mobile, Desktop)
• Metric: Form Submissions (count of event5)

The workflow:

1. You implement tracking: when form submits, fire event5
2. Hits go to Adobe with event5 in each submit hit
3. Adobe aggregates: counts how many event5s per device
4. You query in Workspace: "show me form submissions by device"
5. Workspace returns the report above

Metrics you can't add together

Warning: Not all metrics can be summed.

Example: Bounce Rate = bounces / visits

If you sum bounce rate by page:

| Page | Bounce Rate | (Wrong sum) |
|------|------------|------------|
| Home | 35% | 35% |
| Product | 25% | 25% |
| Total | — | 60% ← WRONG (not 60%) |

The total bounce rate is NOT 60%. It's calculated as (total bounces) / (total visits), which might be 28%.

Lesson: Understand your metric before summing it across segments.

Calculated metrics

You can create new metrics by combining base metrics:

Conversion Rate = Orders / Visitors * 100
Revenue per Visitor = Revenue / Visitors
Average Order Value = Revenue / Orders

You'll learn to build these in Session 9: Analysis Workspace.

Key takeaways

1. Dimensions are categories (rows)
2. Metrics are numbers (values)
3. A report = metrics by dimensions
4. Automatic dimensions/metrics come free; custom ones require implementation
5. Not all metrics can be summed

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Next: L2 · Classify requirements into dimensions and metrics