This brief, 5-minute video by Walter Schloss explains the three main criteria to judge research quality (validity, reliability and objectivity) – unfortunately in German. Important to note is the hierarchy of the three criteria. Validity is the most strict criteria. Any valid measure is also reliable and objective.
Want some insights in how the Cambridge innovation system works? Read here my recently published news article in the Kiel University magazine (unfortunately in German).
If you want to know more about different research designs with references to seminal works have a look at this YouTube page from Graham R. Gibbs (University of Huddersfield, UK). He provides pretty goods lectures on a variety of important methodological topics, such as research quality (e.g., validity, credibility, etc.) and ethics, but also pretty detailed, but good to follow introductions to specific research techniques (e.g., grounded theory and coding approaches, surveys and questionnaire design, case study research and interviewing techniques, ethnography, experiments and quasi-experiments).
This short, 8min video gives a brief introduction to differences typical of research designs comparing particularly case studies, field studies, surveys, experiments and quasi-experiments.