Cultural Heritage domain has opened up to contributions from the users on the web. The contributions are mainly in the form of tags which describe certain aspect of the cultural heritage object. With a wide range of users on the web, it becomes important to determine the quality of the user contributed content before it is published online. However, manually evaluating the quality of these user generated contributions is exhausting in terms of resources for the Cultural Heritage institutions. In this talk, I will describe methods which can semi-automatically predict the quality of tags. These methods address three research questions: How can we trust an online contributor?, How can we assess the quality of annotation process? and How can we trust the contributed data?. The slides for the presentation can be found here.