No wonder the paper keeps falling off

This is an excerpt from a chart of the width of rolls of paper being placed onto printing machines that are producing statements sent to customers.

The supervisor is concerned that variation in the width of the rolls is a cause of breakdown where the paper becomes parted from the tractor reels feeding the paper through.

He has carried out a small experiment measuring at randomised intervals along the roll. The shift in the data is very interesting, and represents different rolls. Not only do the rolls differ in average width, they are nominally supposed to be 440mm wide, so it appears the manufacturing process isn't centred. If this happens regularly, no wonder the paper feed keeps failing,

He resolved to work with the suppliers to reduce the variation between rolls, and therefore reduce the amount of printer downtime.

Confessions of a parking attendant

BBC NEWS Magazine Confessions of a parking attendant: "Right from the classroom, the importance of PAs bringing in high numbers of tickets was stressed. For the new trainees to pass probation, their ticket issuing levels had to be at 1.65 per hour, which is about 10 every day.
I never reached that level and so failed my probation and got a verbal warning. Within the base there were 'leader boards' which listed all the tickets that each PA was getting.
We were divided into teams so if you were bringing back few tickets, like me, you were made to feel bad for letting the team down. Each ticket was �100, so a lot of money is being made by people parking illegally. "

A story of Parking attendants facing pressure to reach arbitrary targets to survive, stress levels ratcheted up with league tables and low wages. They find ways to cheat to give the illusion of achieving more tickets than was actually the case. And what is the purpose of the Parking Attendants? Is it to maximise revenue? Or is it to keep the streets free and flowing? And how does that drive behaviour?

Good control chart - shame about the trend line!

I found this old chart today. It’s a monthly chart of percentage of incidents where a police force has responded to a 999 call within the target time allowed.

The run line tells a story in itself, but the chart is possibly more interesting for its misuse. Note how the person who constructed it has put in upper and lower control limits, but replaced the average line with a line of best fit trend!

Oh dear, oh dear……..