Probability and statistics play important roles in many different areas of science. Find out about probability and statistics in chemistry with help from an experienced chemistry professional in this free video clip.

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Probability and statistics play important roles in many different areas of science. Find out about probability and statistics in chemistry with help from an experienced chemistry professional in this free video clip.

Part of the Video Series: Chemistry & Biology Concepts

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Hi, I'm Robin Higgins and this is probability and statistics in chemistry. Alright, so it's basically just good to have an understanding of how probability and statistics really effects all sorts of science. And so, let's go over one example. So, let's say that you are looking at raccoons and you're counting their stripes. O.k., so what you're going to do, is you're trying to find out how many stripes do most raccoons have on their tails. And let's say the options are three, four, five, six and seven. So, your experiment is basically going to be going out, looking at some cute raccoons, counting how many stripes each have. So, let's say you go out one night and you see a family and it's a family of five. And they have two raccoons with four, and they have one with six and two with seven. And let's say you end your study there. And you say, alright, I found out at the end of my report, is that some raccoons have four, some have six, some have seven. But none have three or five, and four and seven are tied. Well, you really haven't proven that yet because, because of statistics and probability. The probability of you knowing the exact breakdown of raccoon stripes after only fie samples is very low. So, this is something that scientists take a long time to get used to, is that even if you have some data. You don't really know it unless you have a proper study. So, for instance, there's a lot of like urban legends or folklore of how to predict the gender of a baby. So, you may have a grandma who says, oh, if you, you know, have an upset stomach on the fourth month of being pregnant, it means it's going to be a boy. And then, you have that person who gets pregnant and they have an upset stomach on the fourth month and it's a boy. And then, people will be like, it works, you can totally tell the gender of a bay that way. But that's only one study and considering there's only two possible genders, it's just really not very good data. So, let's take a look back at this raccoon study and let's pretend that we did a really good job on it. We went out for a bunch of months and saw lots of raccoons that were in different states and they were all cute and feisty. And then, at the end of it, we found there's actually 305 that had three. Let's say, 2000 that had four and just 10 that had five stripes and maybe 10,000 that had six. And then, only 200 that had seven stripes. So, these are more accurate numbers because we have a larger sample size. So, now you can really tell that most raccoons have six stripes. And that some have four and that really the fewest number is five. So, if we had stopped here, we wouldn't known really any of this correct data. And exactly how many samples you need to have to have your own study work out, is dependent on what you're doing. And there's lots of math to back up how well you know what you think you know. But in general it's important to have this knowledge in the back of your mind. That only a few samples isn't really good enough for science. I'm Robin Higgins and this is statistics and probability in chemistry.