3.3 Data and information
This course is also about information, which in Subsection 2.1 was distinguished from data. Whereas data is a discrete item like a price or the name of a product such as milk, information links two or more items of data to give knowledge: e.g. the price of milk is 50p.
To give a simple example, if I said to you that I was standing at approximately 1 degree 40 minutes and 20 seconds longitude west (written 1°40′20″W), 55 degrees, 4 minutes and 57 seconds latitude north (55°4′57″N), you probably wouldn't know exactly where it was. You would need to know the meaning of the words ‘latitude’ and ‘longitude’ to understand that I was referring to a location.
Assume that latitude and longitude and the signs symbolising roads, towns, and so on are data. Longitude measures distance east and west of the Greenwich meridian in (angular) degrees, while latitude measures distance north and south of the Equator in degrees. When they are combined together in a map they become information, because they answer questions about location. You'd find, for example, that the latitude and longitude I mentioned above refer to a place called Ewe Hill in Northumbria, England. On the map, the printed words ‘Ewe Hill’ are the sign of what the place is called.
Human beings turn data into information through a process of:
creating signs to represent the data;
agreeing on what the signs symbolise;
linking these signs in a variety of ways to create information;
communicating that information to other people.
The distinction between data and information isn't always very clear. Is a bus timetable data or is it information?
In my view, it's a lot of data from which I can extract (if I know how to read it) information about when I need to be at a particular bus stop to catch an appropriate bus.
However, to the person who created the timetable from lots of data about when certain buses arrive at various points along a route, the timetable is information about the system of bus travel in a particular geographical area.
So whether something is data or information depends partly on the perspective of the user. Data becomes information in users’ minds when it informs them (answers a question, such as how to use a bus to get from A to B at a particular time).
Here is another example.
You and I meet on a street corner. You move your right hand towards me with your hand extended but relaxed and open with your palm held perpendicular to the ground. I perceive the movement. That's the data.
I now need to interpret that data. Are you going to hit me? Do I need to dodge or duck? Because you and I may share at least some common culture, I'd interpret this movement as a gesture to shake my hand, and not as a blow about to be struck. I'd be combining my perception of the movement of your right hand towards me in a particular way with other knowledge I have about cultural signs and their symbolism in order to interpret my perceptual data in a way that tells me I need not fear your arm movements. This knowledge (that the gesture is not hostile) is information. Alternatively I could say that I have used information about cultural norms and gestures in our shared cultural experience to decode the sign you have made with your gesture. Either interpretation is valid; indeed, both are valid.
You might consider the implications of you and me not sharing some cultural norm. Many cultures have a gesture that is intended to convey to strangers that one party has no hostile intent toward the other. However, what happens if one party (X) to the exchange doesn't understand the sign intended by the gesture of the other party (Y)? What if there is some additional data or information available (e.g. Y is carrying a weapon)? How then might X react?
You can see from this that information is very important to us as social beings. It is also possible for information to be false, or for a person to have the wrong information, or for information to be ambiguous (subject to multiple interpretations), or for a person to misinterpret information even when it is not ambiguous. One of the themes running through this course concerns whether or not you can always trust data and information to be true and whether or not data and information which were once true will remain so.
Consider a recipe for making a cake. It consists of a list of ingredients and instructions for handling those ingredients.
Is a recipe information or data according to the definitions given above?
In what ways might a novice cook find difficulties in interpreting a recipe?
I consider the recipe to be information, because it answers the question: how do I make a cake? For me the list of individual ingredients and the separate instructions are all data.
There might be many difficulties in interpreting the recipe. The cook might assume that the measurements were in grams when they were in ounces. The recipe could list the instructions in an incorrect order. Also, most recipes in cookery books make assumptions about a cook's prior knowledge; e.g. they may assume that the cook knows what the terms ‘sauté’ and ‘rolling boil’ mean.