 This is part two of lecture two. In this part of the lecture, we're going to be talking about how social psychologists test their theories because that is in the end what we do. We come up with a research question and we want to test a certain theory that we have. So let me sort of walk you through how research works. So first of all, you oftentimes have a question as a researcher, something that's on your mind, something that you're wondering about. And this can be spurred because you read an article, a scientific article, or you had a debate with a colleague, or sometimes you just go about your life and you run into a certain situation and you start wondering, hey, is this something that I could test in my social psychology lab? So we start off with a research question, and that's very simple, a question that we can address in scientific research. Then we start thinking about how could we answer this question. So even before we do the research, we try to come up with the answer. We try to think of, hey, what would make sense? And for that, we use theories. We're going to be talking a lot about social psychological theories. We already discussed some of the theories in the very first lecture. And the theory is basically a sort of a set of related assumptions and predictions that is intended to explain a factor in the world. So we want to explain behavior, we want to explain events based on sort of a set of related assumptions. Then we come up with a hypothesis, and a hypothesis is basically a prediction. What we think is going to happen, a prediction what will happen in a certain situation, and this prediction is always based on a theory. So you first need a theory and then you can come up with your prediction or your hypothesis. And then finally, you run a study, and you run a study in which you test the hypothesis. And the outcome of the study is always a prediction of the hypothesis or a rejection of the hypothesis. So you can either say, yes, my prediction, my hypothesis was correct, or at least the results that I obtained are in line with my hypothesis is often what we say. Or we can say we do not find support for the hypothesis. So let me give you an example, something that I studied myself. So my research is on relationships. So one factor that could be of interest of me, this was actually a sub question of one of my research lines. Does selectivity, so how selective, how picky you are when choosing a partner, does that depend on gender? So is there a difference between men and women in selectivity? Then you can start thinking about a certain theory that could predict this. Well, one theory that could have sort of predictions about this question is evolution theory. Evolution theory would probably argue that women are more selective, more picky, more critical when it comes to choosing a partner than men. And that is because the investments that women have to make when choosing a partner are bigger, they run higher risks, they are more vulnerable in relationships. And also, if we go one step further, if you decide to start a family with a certain partner, then a women run a higher risk because if you choose the wrong partner and you end up being pregnant and this partner leaves you or treats you bad or treats your children bad, then you're really in a very difficult situation. So according to evolutionary theory, women should be very selective when it comes to choosing a partner. Okay, so let's imagine this is my hypothesis, then I can study this. So how can I study this question? There's actually several ways that you could use. I will now describe three different methods that we could use to answer or to try to study this question. The first one is using archival data. The second one is using observations and finally we can also rely on surveys. Okay, so let's start by talking about using archival data. So this is a dating application or actually sort of a fake dating application which looks like the dating app Tinder. For some of you it looks familiar maybe. So in this dating app you see profiles of potential partners and you can choose to either accept this partner which would be swiping to the right or you can reject this partner and that would be swiping to the left and that's what this lady over here is doing with all the profiles she sees. She is being very selective, she's being very picky. So using data that comes from for example a dating application such as Tinder, so data that's actually available that's sort of in archives that will be relying on archival data. So you don't have to run a study yourself, you just have to look up the numbers and you have to see whether you can find information that can be from archives of a dating application but also for example in the newspaper or using other archives to get information to answer your research question. This would be one way to go about this and if we would do so we will probably see that our expectation is correct that women are indeed more picky than men. Here you see some swipe statistics and the red parts of the bar are the rejections, the passes, the swipe to the left and here you see that females are indeed very selective. 95% of the profiles they see they swipe to the left. These men or oftentimes men sometimes women don't stand a chance. For men they are used different strategies, they are less selective and for them it's pretty much 50-50 who they select and who they reject. So yes, if you use this methodology then you will find that indeed women are more selective than men. Maybe you don't want to rely on archives, maybe you really want to test data yourself and what you then could do is use observations. You could for example go to a bar and you can watch behaviors of men and women in a bar and see how picky they are when it comes to choosing a partner. If you would do that you can do a field study in which you actually go to a bar and test your hypothesis. That would be quite a fun study to do, right? Then finally another method that you could use is relying on surveys, questionnaires, that's really a favorite of social psychologists. We love questionnaires and in questionnaires you just basically ask people how picky are you, how selective are you when it comes to choosing a partner and I did this in the past and I can confirm that indeed also when you ask people women indeed also say that they are more selective when choosing a partner than males. So these are the different ways in which social psychologists can gather their data.