there's levels of measurement when you're getting some data you'll be asked a lot of questions on your homework about which which level is this and I'm going to go through in order um but I have them on this page nominal is data that the name a label or a category and you couldn't put them in order for example the ice cream one I was talking about if I ask you all your favorite flavor of ice cream you're all going to give me a name for your favorite flavor but I just I wouldn't know which way to order them in like just chocolate come before strawberry we don't I mean after I counted maybe I could order them right but there's no order to those um categories of anything if I asked you your student ID number huh that's a number but what does your student ID really what is it really it's a list of numbers I wanted to represent ative it just represents you as a student it's kind of the same thing as your name really right your student ID number is really your name like like your social security number is like your name it wouldn't make sense to average your social security numbers say hey the average in my class is this number I mean it doesn't make sense because you're really talking about names so uh nominal are categories that seem obvious but sometimes they're numbers that we use as names the phone number that uh who came up with that Celia right was that you said phone number earlier phone numbers are really names too this is the number in my phone that goes with this person's name right so that would be another example of nominal so there's any kind of answer that's a category or really is used as a label or category that's where you actually have an order but you don't know the difference between the uh between the categories for example let's say I asked you to rank um these drinks putting three drinks up here coffee water and milk I don't know and I asked you to rank them in order of your favorites one two and three who wants to volunteer their answers what do you got what's your favorite water this is your number one yeah this is her order yours might be different that's okay so she has these in order but does she like coffee like water three times as much as coffee like or does is does she like water and milk almost the same but coffee is a far distant third you know what I'm asking here it's like we don't know what the difference is I probably would agree with her if it was my list as well and I would say yes water's my number one for sure and milk is pretty close to here but coffee is probably on the bottom corner of that board over there if I listed all the other drinks in the world I don't drink coffee I can't stand coffee bring tea every day and so coffee is a very very distant third for me you know it's my third and her third but we don't know the differences so that's what it means when it says the differences are meaningless you can put them in order but you can't really compare one to the other and know how much better or worse it is we do this when you know you go on and you rank they rank movies and give them Stars you know from one to five stars a five-star movie versus a one star movie does that mean it's five times better I mean or how much better is the four star versus you know it's better but you don't really know the differences so all you could do is put them in order but not really explain the differences that's ordinal right there ordinal you can put them in order but not make any sense of the differences then the next step up so each of these is a step up it's kind of the last one with a little bit more detail thrown in the next one is interval which is a little bit hard to understand it says you can arrange it in order and differences are meaningful but there is no natural zero or starting point so I'll give you one of my easiest examples of interval that would be the temperature so I don't know the temperature this morning was not scorpion yet so here's my beautiful picture of the thermometer what was the temperature this morning maybe 70 16 68. go around probably 70 by now probably faster all right so 70 is the temperature and maybe somewhere else this morning it's 30. not here but somewhere it's probably 30 somewhere in the world I'm talking about Fahrenheit degrees it could even be zero somewhere especially when we get into the later part of the fall in the winter and it could be negative 10 at some point right all this makes sense when you talk about temperatures so we can actually talk about the differences between us it's 40 degrees warmer we know what one degree is I mean we can't necessarily feel it but we know how to measure what degree warm there's a difference between like you said 68 I said 70 that's two degrees different so the differences make sense so that's what it means here when it says you can put them in order like smallest to biggest and the differences are meaningful now but there is no natural zero or starting point there is a zero but when we say a natural zero zero means nothing and if I asked you how much money you have and you told me you have zero that means you have no money right and if I ask you how much of your homework have you done and you say zero that means you have to start your homework yes but if I ask you what the temperature is and we say zero that doesn't mean we go outside and feel nothing all right now you still feel so they have to feel pretty cold if you go outside especially dressed like this so it doesn't mean the absence of something right and when you're talking about temperatures it's just kind of a number on a scale that means something it doesn't mean you have nothing you have no temperature and you wouldn't say that you know this is more than twice as hot as this I mean we don't talk about temperatures like it's twice as hot yesterday as like temperatures don't work that way right because we don't have a zero that means no temperature everyone all right with this example has to do about what it means differences are meaningful and no natural zero the only examples I can come up with I have a student last semester who gave me a third one I remember what it was only ones I can ever come up with until I learned a new one that I've already forgotten are temperatures and years like I you know you were born in the year 1995. the year is zero we're not going to get into religion the year zero was not when though everything started counting right that's not the when time began I think most of us would probably agree with that yes what about women's genes you got a size zero but that doesn't mean there's nothing there's a new example sizes for jeans there's two four six and they have a zero for people who are skinnier than skinny zero doesn't mean you don't exist and you don't wear jeans you can put them in order right size two is bigger than a size zero a zero doesn't mean yours you don't even exist you still get to wear those jeans I love it love it will give me new ideas so now the only examples I can come up with today because I can't remember my other one our temperatures years and women's jeans there might be other ones okay I just want to put them I always want anyone from last semester well right though how that means what I mean by no zero but the order does make sense okay there is a zero but not what we call it a natural zero means nothing right invisible jeans when they're size here that would not be recommended all right so that's interval and then ratio is everything else you've ever seen um money is a perfect example if you have zero money you know you have no money and if you have ten dollars and she has twenty dollars she has twice as much money as you right 10 versus 20. the word ratio is you can talk about twice as much half as much and that makes sense where here I couldn't talk about something being twice as hot or half as hot with these numbers right but money is a good example Heights is an example right if you measure something to zero it has no height whatsoever zero is the and even a negative wouldn't make sense in that case I have a negative height so Zero's the beginning of where you start measuring you could have negative money this means you owe money instead of you get money right but ratio is pretty much everything else you've ever seen and zero means you don't have it whatever the hit might be questions about painting