Small schools and multiple criteria

The county of Devon, where I live, has many areas where there are small villages and few towns. The population is concentrated in the towns and cities, but a significant number of people live in the villages and commute, or work locally. Today there has been some discussion about the provision of education for children and a report about Devon has identified several primary schools with fewer than 30 children in the whole school (age 5 to 11) and one secondary school with less than 500 children. The report raises the question about the viability of such schools, based on the cost per capita. Fairly obviously, education is an area where there are economies of scale -- you need a couple of teachers at least in each school, you need buildings and these must be heated and lit whther there are 10 children or 50.

So should small schools be closed and the pupils transferred to larger ones, where the cost per child will be smaller? I suggest that this would make an interesting question for an examination on multiple criteria optimisation or soft systems. There are other factors than the cost per capita to consider. Schools in small communities are a social focus for those communities. Families and children belong to them. What are the effects on children if they have to spend an extra hour at each end of the school day in travel?

Listening to the radio discussion this morning reminded me, once again, that operational research needs to be multidisciplinary. The figures matter, but behind those figures are people with needs and aspirations that cannot be measured.

The Bishop and Wartime O.R.

Earlier this year, Bishop Graham Leonard died. He had been Bishop of Truro (next door to Devon) and then a very distinguished Bishop of London. In his obituary in the "Church Times" there was a one-sentence reference to the fact that during 1944-1945 he had been seconded to the Army O.R. group. No further explanation, and I wondered how many of the readers of the paper would know what O.R. was. A further search led to a national newspaper recording that he had worked on fuses. That led to yet another search using the keywords "Operational Research" and "fuses" which didn't turn up any more about the late bishop.

However, the search turned up a reference that in 1944-45 the Army O.R. group had been working on fuses used against the V2 "flying bombs". And that reference was also fascinating, as Dorothy Hughes one of the first four lady "Chelsea Pensioners" had been involved with that section.

Automated attendants

I learnt a new technical term today: "automated attendant". It describes the telephone systems that are familiar (and often infuriating) in the 21st century. The caller dials the number, and an automatic service directs the caller to select a service using the buttons on the telephone. There are all sorts of jokes about this and I found a You-Tube video of the song "Press one for English".

My curiosity was aroused when I rang the offices of a national club in the UK. The club advertises that it has 60,000 members. When an automated attendant answered, I wondered what the economies of such a system might be. At what size of organisation does it become worthwhile to install one? Has anyone done an O.R. study of this? There needs to be a measure of the number of calls that come to the office per day, both on average and -- for a club -- the peak times for renewals. And there's questions of the number of people in the office whose job includes answering the phone. It could be an interesting study. The model would be straightforward, the data collection more challenging. However, I have discovered that the systems are so cheap, that they are probably worthwhile for more offices than currently use them.

Operational Research in Iran

A new journal of O.R. has been launched, and has now published two issues. This is the Iranian Journal of Operations Research, published from Tehran. On first glance, its contents are generally theoretical, but that is true of many other O.R. related journals. The first abstracts from it will appear in IAOR in early 2010.

What is not clear is hows strong the fledgling O.R. socety is in Iran. The web address suggests that there may be plans for it to develop, but the English version is limited at present.

The best statistic I have heard for a long time

BBC Radio 4 has a flagship news and current affairs programme every weekday morning called "Today". Following one interviewer's comment, the presenter commented "The best statistic I have heard for a long time". He then paused and added words to the effect that the statistic was not good news, but had been presented in a clear way so that the meaning was easy to understand. It strikes me that those of us who work with mathematical models could learn from this example.

The interview had been about the social deprivation of parts of the east of London, and the comment was made: "for every tube stop on the Jubilee line [on London Underground] going east, from Westminster to Canning Town, life expectancy decreases by one year". It is not good news. But the information is conveyed in a way that is clear, simple and easy to assimilate. It is not cause and effect. Underground stations do not affect life expectancy. But one has a clear sense that the further you travel along the line, the more social deprivation, leading to lowered life expectancy, you will encounter. And the figure of "one year" is probably a rounded version of the data ... but for the purposes of this graphical illustration, it is precise enough. Someone has found a way to present information, which is of use to planners, in a way that is easy to take in. So we can learn from the example.

But, as usual, the story above is only part of the story. The statistic has been created by using limited information and extending it. The data which had been used said that the life expectancy for residents near Westminster station was seven years more than that for people living near Canning Town. They are eight stations apart. Nobody has written abot the life expectancy at those intermediate stations. All that has been done is to draw a straight line between the two extremes and assume linearity. Even though the method is not rigorous, it is still graphic. How can we learn to strike a balance between rigour and clarity?

Optimising a sound system

A curious story came my way, which is a piece of optimisation which has never been (and probably never will be) written up as an academic paper. But that's true of much applied O.R. all the time. Even academics who need to publish find that some of their studies are simply unpublishable. The story came from Dustin Curtis' blog.

He described meeting a sound engineer who set up ambient sound systems for Walt Disney World. Here's an extract:

In the mid 1990’s, the park started researching the problem. It would eventually find no existing solution, so the engineers had to design and construct, on their own, one of the most complex and advanced audio systems ever built. The work paid off: today, as you walk through Disney World, the volume of the ambient music does not change. Ever. More than 15,000 speakers have been positioned using complex algorithms to ensure that the sound plays within a range of just a couple decibels throughout the entire park. It is quite a technical feat acoustically, electrically, and mathematically.

Just think what O.R. tools would be needed for that sort of optimisation and design!

Smeaton's Tower

On 16th October 1759, Smeaton's lighthouse on the Eddystone Rocks (14 miles out of Plymouth) was illuminated for the first time. The original lighthouse has been dismantled and re-erected on Plymouth Hoe.

To mark the anniversary of this pioneering building, it was illuminated by candle-power once again on the evening of 16th October 2009.


The lighthouse featured on British one penny coins until 1970:



Why mention this in a blog about operational research? Logistics. 250 years ago, the lighthouse was illuminated by 24 candles. Three lighthouse keepers had the job of ensuring that these were lit all night, every night. They were dependent on supplies from the mainland, and the lighthouse was notoriously difficult to reach. Sometimes the keepers went for weeks without fresh supplies. So, here's the problem: how did the stock controllers plan for candles, food and supplies for the lighthouse? Apart from fresh fish, there were no other sources of food on the Eddystone Rocks. Sometimes the keepers were starving when boats reached them from the mainland. It makes academic models of inventory management seem ... academic.

And now for something different:



The Keeper of the Eddystone Light

My father was the keeper of the Eddystone light
And he slept with a mermaid one fine night
Out of this union there came three
A porpoise and a porgy and the other was me!
Yo ho ho, the wind blows free,
Oh for the life on the rolling sea!

One night, as I was a-trimming the glim
Singing a verse from the evening hymn
I head a voice cry out an "Ahoy!"
And there was my mother, sitting on a buoy.
Yo ho ho, the wind blows free,
Oh for the life on the rolling sea!

"Oh, what has become of my children three?"
My mother then inquired of me.
One's on exhibit as a talking fish
The other was served in a chafing dish.
Yo ho ho, the wind blows free,
Oh for the life on the rolling sea!

Then the phosphorus flashed in her seaweed hair.
I looked again, and my mother wasn't there
But her voice came angrily out of the night
"To Hell with the keeper of the Eddystone Light!"
Yo ho ho, the wind blows free,
Oh for the life on the rolling sea!

by: Charles Wingate