The ideas of first year university students about measurement in the physics laboratory are explored. Student responses to written probes administered at the beginning of the year are compared to those written after a 12 week laboratory course. The 'point' and 'set' paradigms are used as a model to analyse the responses to the probes. At the heart of the point paradigm is that both action and reasoning are based solely on individual measurements in a data set. On the other hand, subscribing to the set paradigm implies an understanding that a series of measurements are to be viewed as a collective that can be modelled by theoretical constructs, such as the mean and standard deviation. The degree of consistent use of these paradigms by individual students across the sets of probes is investigated. Implications for effective teaching interventions in the physics laboratory are discussed.