After the Christmas holidays we started with 111 pieces of paper filled with hand written information.
All the information had to be encoded in a digital way.
We chose to set up an Excel sheet. The encoding process was shared amongst all the members of our group. Therefore the raw data was in within one afternoon.
Pretty quick it became obvious that not everybody of the interviewees had been willing to give us all the information that we had asked for. What a bummer! It turned out that 60 out of the 111 questionnaires had insufficient information regarding the students’ street address.
We intended to use the street address to map the students’ homes. With such a map it would be easy to design an efficient route for a school bus or to advertise car sharing in suburbs where there was a high density students
But what to do now?
We couldn’t proceed and lose 54% of our data!
Luckily the city of Windhoek entertains an online cadaster map. Here an amazing amount of information about other people’s property is easily accessible by the public.
Apart from the street names, house and Erf numbers, you find the name of the owner, value of the property, water and electricity usage and lots more.
To us only the streets with house and Erf numbers were of any interest.
The Namibian Erf number is a unique number that every piece of land gets assigned to, so it can be solely identified by its Erf number. The GPS coordinates for latitude and longitude of Erf numbers were recorded with the CO-ORDS tool.
With the help of this online cadastre map we were able to fill in the missing street address data for all households but four. If the house number and street name was given we were able to find the corresponding Erf number and vice versa.
Now we used a geographic information system to map the data. This process was painfully slow and very labor intensive because each of the 110 points had to be mapped individually.
But in the end we produced a map that showed for the first time in a graphic way where the students of DHPS lived.
On the map you can see that most of our students live within or around 2.5 km away from school (indicated by the outer circle). The map points are color coded depending on the time it took each student to travel to school.
If you look carefully you’ll notice that some interviewees weren’t too honest or made mistakes. For example: there are a turquoise and a green spot in Katutura in the northern part of Windhoek. This would indicate that these students traveled between two and five minutes to get to school, which obviously can’t be true.
But this map shows what a powerful tool a geographic information system is.