
Together, we are recording our dissent.
This is a simple primer on counting crowds based on the Jacob’s Method.
For No Kings Day, we are attempting to release an estimate by that evening. You can help by submitting your counts by 5:00 PM PST on June 14.
For crowds under 500, do a manual count.
Recruit a friend to double check or help count.
Before you begin, divide the area into blocks by similar crowd density. You will repeat these steps for each block. Usually, the crowd nearest the stage/steps is more dense. It then fans out into a looser density the further the crowd is from the stage/steps.
Again, repeat this process for each block that shares a crowd density.
ONE - FIND THE AREA
Length x Width = Area
NOTE: Only measure the space occupied by protestors.
METHODS FOR MEASURING
TAPE MEASURE OR PACE IT OFF
2. ON YOUR COMPUTER
Several map softwares allow you to measure the area.
3. USE AN APP
Find My Distance (measures length and area)
GPS Fields Area Measure (measures area)
Here are two examples:
In the first, the app calculated the area.
In the second, you would multiply length x width.
382 ft x 202 ft = 77,162
TWO - DECIDE THE CROWD DENSITY
SPEAD OUT
People are roughly an arms length away from the body of the next person side-to-side with room in front and behind them. Imagine a 5ft by 4 ft box around them.
= 20 sq ft per person
LOOSE
People are roughly an arms length from the body of the next person. Imagine a 5ft by 2ft box around the person
= 10 sq ft per person
MEDIUM
If you drew a box around them, it would be about 2x2 ft
= 4.5 ft per person
DENSE
People are shoulder to shoulder with little room in front and behind
= 2.5 ft per person
MIXED
Remember, crowds are rarely a uniform density. Repeat this process for each block that shares a similar density.
THREE - DIVIDE 1 by 2
AREA ÷ CROWD density square footage
= CROWD COUNT
77,162 ÷ 10 = 7716
Crowds will not be one density
Let’s imagine half of the area being medium density and half being loose.
38,582 ÷ 10 = 3858
38,582 ÷ 4.5 = 8573
ADD them together 3858 + 8573 = 12,431
Let’s say THE AREA IS AN ODD SHAPE
To measure this, you break the area into squares or rectangles. A T-shaped area could be broken into the horizontal and vertical line.
Unless you did a manual count, enter 20% under your count as the low estimate and 20% over as the high estimate.
EXAMPLE
From this Facebook post from April 5, we can estimate the crowd size.
FIRST, I divided the space into blocks with a similar crowd density.
SECOND, using Cal Map, I determined the area for each block
10,516 sq ft
10,774 sq ft
10,182 sq ft
51,343 sq ft
THIRD, determine the crowd density for each section. Section one is medium. Two and three are loose. Four is spread out. The stragglers would fill in the gaps. Obviously, on the ground, we could get a better estimate.
FOUTH, divide the square footage by the density.
10,516 sq ft / 4.5 = 2336
10,774 sq ft / 10 = 1077
10,182 sq ft / 10 = 1018
51,343 sq ft / 20 = 2567
ADD them together to get the estimate of 6,998. This estimate is fairly near the reported crowd size by the local news.
NOTE: As we are only making an estimate from photographs, we cannot be certain of the crowd density. That’s why determining it live is vital.
Length x People Per 10 ft = Count
See methods for measuring area above.
Length ÷ 10 x People Per 10 ft = Count
548 ft long
5 people per 10ft
548 ÷ 10 = 54
54 x 5 = 270
IMPORTANT: Calculate for each side of the street occupied
Length ÷ 10 x People Per 10 ft = Count
254+254+353 = 861 ft long
8 people per 10ft
861 ÷ 10 = 86
86 x 8 = 688
Calculate for each side of the street.