I have been reading a 2025 book by Bill McGowan and Juliana
Silva which is titled Speak, Memorably: the art of captivating an audience. It’s
not awful, but it’s not great either. There is no index. On August 2, 2025 I posted about A bogus
car story from the 2025 book Speak, Memorably.
On page 10 of that book they state that:
“….in the chapters that follow, we commissioned a survey by
the Clarity Media Group of over one hundred people. The respondent pool was
comprised of full and part-time employees between the ages of twenty-five and
sixty-five.”
There are 31 horizontal bar charts shown in this book on
pages 11, 15,21, 27, 36, 38, 55, 58,60, 71, 113, 114, 135, 139, 153, 155, 168,
183, two on 185, 194, 197, 199, 204, 214, 215, 226, 228, 229, 243, and 244. They
are shown in monochrome, and only are 3.3” wide by 1.5” high. The percent is
labeled at the center of the bar, and the description of the question is to the
right of the bar.
My slightly different Excel version of the chart on page 11
for Do You Consider Your Public Speaking Skills at Work Important? is shown
above. But those bars are not presented in what should be their order, with the
most significant and largest percentage placed at the top. My revised version also
is shown above.
Another example from page 168 about How Do You Determine
What Your Audience Wants to Know? and a corrected version are shown above.
18 of 31 charts have this incorrect order, those on pages
11, 21, 27, 36, 113, 139, 153, 155, 168, 183, 185 bottom, 194, 199, 204, 214,
215, 228, and 229.
And as shown above, the chart on page 21 for How Often Do
You Know with Certainty the First and Last Sentence of Each Slide? has silly labels
from top to bottom of: Never, Rarely, Sometimes, and Frequently. That is
opposite to what should be: Frequently, Sometimes Rarely, Never. They used the
same sequence on pages 27, 113, 139, 155, 199, and 215. Also the chart on page 194
has Never, Seldom, Occasionally, Frequently.
Back on September 6, 2022 I blogged that we should Beware of
surveys with small sample sizes, which have large margins of error. There is a
Wikipedia page about Margin of error. For a typical national survey with a sample
size of 1,000 the margin of error is 3.1%. For a sample size of 100 the margin of
error instead is 9.8% (as is shown above
in my revised version for page 11).
Is the difference between the largest percentage and the
second largest percentage twice the margin of error (or 20%)? That only is true
for ten charts, those on pages 36, 55, 58, 71, 135, 139, 168, 183, 185 top, and
215. Not the other 21 charts!
I first mentioned the mythical Bar Chart Police (and showed a
version of their badge) in a post on November 3, 2023 titled Five of six
British age groups are more confident about public speaking after COVID.