Collecting and Presenting Data
Data are the key to many important management decisions.
Is a new product selling well?
Do potential customers like the new advertising campaign? Should we launch a new product?
These are all questions that can be answered with data. We begin this course with some basic
methods of collecting, representing and describing data. In this first lecture we will look at
the different kinds of data that exist, how we might obtain these data, and basic methods for
If we were buying a new car, it would be useful to know how much it was going to cost to run it
over the next three years. Obviously, we cannot predict this exactly as each individual car and
each user will be slightly different. Collecting data from people who have bought similar cars
will give us some idea of the distribution of costs over the population of car buyers, which in
turn provides us with information regarding the likely cost of running the car.
Most clothing now comes in essentially standard sizes, but from where do these standards come?
By sampling from the general population as a whole, standards can be set around the most
common sizes. We cannot say that an individual is exactly a standard size. However, we
say that they will
fall within a range either side of a standard.
The quantities measured in a study are called
and a particular outcome is
. A collection of observations is the
. The collection of all possible
outcomes is the
If we were interested in the height of people doing management courses at Newcastle, that
would be our random variable; a particular person’s height would be the observation and if we