EN
In the paper, the results of study on the influence of inadequate information on the estimation of survival curve using the Kaplan-Meier method has been presented. The authoresses carried out an analysis of time of being unemployed for people signed off from the District Labour Office in Szczecin in the 4th quarter of 2006. Survival analysis methods allowing censored data were used. The described study concerns people that had been signed off due for reasons other than finding a job. In their case one can suppose that they had taken a job but did not report it to the office. This information may essentially influence the course of survival curve describing probability of being unemployed (in register) for a specific period of time. For calculations the 'Survival Analysis' module included in the Statistica program was applied.