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Why Do People Lie With Charts?

In Three Ways To Lie With Charts, we saw three common ways in which people lie with charts.

To recap, they are:

  1. Slippery Slope Slide
  2. Floating Origin Fraud
  3. Dual Axis Deception

In this post, I'll speculate on the reasons for lying with charts.

The most obvious trigger for lying with charts is that, people are out to sell some product, service or point-of-view and run into facts that threaten to derail their pitch.

But, after reading my previous post, some kind-hearted souls among you argued that lying is not the only motivation for people to use misleading charts.

I took that objection seriously and did a serious exploration of the other likely reasons.

This blog post is the result.

Slippery Slope Slide

The label of the stock price (256.3) on the last day has a typo. But, with novel ways of lying with charts coming up every day, what do I know?

Floating Origin Fraud

This could be a problem caused by default settings in Excel.

Back in the day, the Y-axis of a line chart on Excel would begin at zero by default. Whereas in recent versions, I'm noticing that the Y-axis begins, by default, near the smallest value of the dataset on that axis. While the change in default setting has resulted in a chart that makes better use of white space, the appearance of the chart drastically comprises the integrity of the data. For that reason, it's wrong.

Let me illustrate this problem by using this Excel spreadsheet, in which the data on the Y-axis ranges from 81 to 86.






I used the following default chart settings in the 'Default Chart' tab: Select both columns; Insert > Scatter Chart > 2nd Option > Default chart settings.

As you can see, the Y-axis on this chart begins at 80, which is just one unit lower than 81, the lowest value on the Y-axis data series; and the chart that results is misleading (Exhibit 1).

EXHIBIT 1: Default Excel Settings

To fix this, I changed the settings in 'Modified Chart' tab as follows: Select both columns; Insert > Scatter Chart > 2nd Option > Change chart settings > Layout > Primary Vertical Axis > Primary Vertical Axis More Options > Change Minimum Value from Auto to 0; Change Maximum Value from Auto to 100.

Now, the Y-axis begins at 0, as it should, and the chart conveys the correct picture (Exhibit 2).

EXHIBIT 2: Modified Excel Settings

Dual Axis Deception

I thought this chart was an outright attempt to mislead readers. But, then I found that Excel was the culprit again.

I don't know how to change the default settings to prevent this dual-axis chart from being misleading and couldn't be bothered to learn.

Since I can't "beat 'em", I've decided to "join 'em", with the following misleading contribution of my own that resonates well with my advice that Fintech Shouldn’t Stop Chanting The Disruption Mantra (Exhibit 3).


Ha ha:)


Typo. Using default settings blindly. Reluctance to learn a tool correctly.

These are the reasons for the aforementioned misleading charts (assuming that lying is not).

The common factor behind them is laziness or casual attitude aka sloth.

Lying or sloth? Take your pick.

At least lying is not one of the seven deadly sins.


Comments: (5)

Melvin Haskins
Melvin Haskins - Haston International Limited - 27 August, 2019, 11:16Be the first to give this comment the thumbs up 0 likes

Thank you for updating Darrel Huff's 1954 book - How to lie with statistics. He described the Gee Whiz Graph, which does not have zero on either axis, so the presenter can make the graph show whatever they want it to show.

I am continually amazed by the number of newspapers and websites that use Gee Whiz graphs to prove whatever point they want to prove.

Ketharaman Swaminathan
Ketharaman Swaminathan - GTM360 Marketing Solutions - Pune 27 August, 2019, 15:09Be the first to give this comment the thumbs up 0 likes

LOL. I read "How To Lie With Statistics" over 40 years ago and forgot he had given a name for Floating Origin charts! I used to think the same way about newspapers and websites until I tried to plot a few charts on Excel myself. As described in the post, Excel has changed it default origin. It's no longer at 0,0. But newspapers and websites are responsible for changing it back to 0,0 but they seem to be conveniently asleep at the watch.

Melvin Haskins
Melvin Haskins - Haston International Limited - 28 August, 2019, 00:201 like 1 like

I keep a copy of How to Lie with Statistics on my desk. It was compulsory reading on degree courses in England in the 1970s.

Other headings to remember:-

The sample with the built in bias

The well chosen average.

The semi-attached figure.

There are many more terrific examples of massaging the figures. This small book (124 pages, including pictures) should be compulsary reading for anyone reviewing information.

Ketharaman Swaminathan
Ketharaman Swaminathan - GTM360 Marketing Solutions - Pune 28 August, 2019, 13:24Be the first to give this comment the thumbs up 0 likes

Thank you for highlighting. I recall a few of them. I think "Sample with built in bias" is somewhat similar to the technique I termed as "Pixie Dust Sample" in Beware Of Committing Harakiri By Lying With Big Data

A Finextra member
A Finextra member 29 October, 2019, 16:01Be the first to give this comment the thumbs up 0 likes

Very good artcle/Psot. How much the impression changes by depicting the numbers in a certain way. In a day where both AI and Machine Learning are being promoted or is already in use by various companies, I hope there is some thought given to the underlying data and its representation. It is easy to get carried away and falisfy information. There is a lot involved in achieving Data Integrity, Lineage and Model development.

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