WEBVTT
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this question shows you a couple of different airlines and
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the number of complaints that they get the first part
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ask you to just average the total number of complaints
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we know that the mean is explores. Some of
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the X is divided by and the total number of
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ah, of data points that we have using a
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calculator, we can sum up all these exes to
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find that is 303,484 and they're obviously 10 data points
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. So we know that X bar is 348 0.4
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complaints. It also wants us to find the mean
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are the median. Um, we know that when
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n is 10 the median is gonna be the average
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between X five and X six. That's gonna be
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so. X five is the fifth highest. Next
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66 is the sixth highest. Um, and so
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we want to find that the middle of those two
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. So we have X five next six finding the
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average, um, that is gonna be 350.
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He's already in orders of 350 is the fifth highest
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plus 140 Niners with six highest dividing that by to
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the median we now know is 249 0.5 complaints now
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for PS. Are these measures of central tendency of
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really good other relevant? Are they helpful? Well
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, consider what we're measuring in our first column.
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We have our first real. We have Delta Airlines
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, and in our very last year we have Alaska
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Air. Which do you think gets more passengers?
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Obviously, Delta flies Ah, lot more people every
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day than Alaska does. So it's natural that they'll
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get a lot more complaints. What we're really after
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is how many complaints per passenger are these airlines getting
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because obviously more more passengers will correlate to more complaints
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. So this means that no, it's not a
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great measure of central tendency. And actually, we
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want to use what's the next column? Which is
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complaints per 10,000? Here we have complaints per 10,000
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and asked us again to find the mean I mean
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, we already went over This is this some of
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X over N and is still 10 and now when
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we sum up, all of our exes will get
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11.87 complaints per 100,000 so the mean that mean for
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every for these top 10 airlines is that on average
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they'll get 1.187 complaints per 1000 passengers. 100,000 passengers
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. Now what's the median again? Will find x
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five and x six thes aren't in orders. We
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gotta make sure that we're finding the right ones,
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but will have I think, x five that there's
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no now going from lowest to highest X 50.87 and
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x six is 1.56 If we do buy those way
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too, we'll get the median and we'll find that
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it is 1.215 Now, is this a better measure
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of central tendency? Well, yes. With this
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way of measuring complaints, we are taking into account
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that some airlines get a lot more than others.
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And when we take away that factor now, we
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give each airline equal weight. And so we're finding
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really the average amount of complaints, um, per
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airline per passenger and your final answer