<commit_before>---
title: Getting Reliable Visual Metrics
date: 2016-06-08 11:26:00 Z
categories:
- '2016'
tags:
- webpagetest
- speedindex
comments: true
image:
  feature: "/uploads/ads_hero.jpg"
layout: post
---

Visual metrics such as Speed Index, render start and visual complete are the best proxies we have for user experience. Unfortunately two of these are totally thrown by rotating carousels, popups, cookie banners and adverts.

To give an example, below is the homepage of Transport for London loading at Cable speed from London. It's clear that the main content of the page is visible by 6.5 seconds. The metrics we get from WebPageTest don't tally though, with visual complete coming in at almost 12 seconds.

<figure>
<img src="/uploads/tfl_6-5.JPG"/>
<figcaption>Filmstrip section showing TfL visually complete at 6.5 seconds.</figcaption>
</figure><commit_msg>Updated Getting Reliable Visual Metrics<commit_after>---
title: Getting Reliable Visual Metrics
date: 2016-06-08 11:26:00 Z
categories:
- '2016'
tags:
- webpagetest
- speedindex
comments: true
image:
  feature: "../uploads/ads_hero.jpg"
layout: post
---

Visual metrics such as Speed Index, render start and visual complete are the best proxies we have for user experience. Unfortunately two of these are totally thrown by rotating carousels, popups, cookie banners and adverts.

To give an example, below is the homepage of Transport for London loading at Cable speed from London. It's clear that the main content of the page is visible by 6.5 seconds. The metrics we get from WebPageTest don't tally though, with visual complete coming in at almost 12 seconds.

<figure>
<img src="/uploads/tfl_6-5.JPG"/>
<figcaption>Filmstrip section showing TfL visually complete at 6.5 seconds.</figcaption>
</figure>
{'fraction_non_alphanumeric': 0.07519640852974187, 'fraction_numerical': 0.029180695847362513, 'mean_word_length': 4.554517133956386, 'pattern_counts': {'":': 0, '<': 13, '<?xml version=': 0, '>': 13, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'dir': 'git-commits-cleaned', 'id': '1462206', 'n_tokens_mistral': 540, 'n_tokens_neox': 483, 'n_words': 243}