Learn About Misleading Graphs
In this lesson, let’s learn to identify misleading graphs. We will see why all graphs do not give out a clear picture. So the first one, we need to explain why this graph is misleading. And this is a trick used by advertisers by the way, just to make you believe certain things are true when there in fact not. So for example, this shows us the prices of tickets 1991 to 2001 for baseball and basketball.
If you can see it looks like the difference between a baseball and a basketball game, ticket price is huge between ’91 and 2001. But let’s look at the real data. This is about $9.00. This is about $21.00. So lets a little over twice that but if you look the relative size of the balls. This looks like five times bigger than this. Similarly this is about $20.00 and this is about $51.00, right. But this looks way bigger than this, right. So it’s misleading because the size of the balls, right misleads us, instead of looking at just the height.
If we had use bar graphs, we will see that this twice the height of this. But this make it looks as way bigger than this, right, so this one is misleading. Let’s look at the second one. Why is this one misleading? Which one is misleading? Both show monthly profits for a corporation from October to march, right. Which of the one is misleading? Well, this one shows us profits from $14,000.00 to $17,000.00 intervals up $500.00. So it shows us a steady climb.
Here, first we see an interval of $500.00 then we see an interval of $100.00. So these have an interval of $100 and here we have $500.00. So it makes it looks like the profit climbed faster. But the reality is they didn’t, right because this one, the profits climbed to 15,400 here they climbed to 15,400 as well. If we have kept the vertical axis intervals the same, this is the correct graph. This is misleading. If it’s actually correct but when we look graphs, we’re looking for trends. This one makes it seems like the profit grew fast where this is the actual value.
Again, the differences, the intervals are consistent here. The intervals are not consistent here. First, its starts at $500.00 then instead a $100.00, okay. So which one is misleading? B is misleading, okay. Let’s look at the third one. Both bar graphs show a percent of people in California, Maryland and Michigan and Washington who use seatbelts. Which graph could be misleading?
Well, at here it looks like all of four them are closed, right. It’s from 82% to 87%, very close, right. Here, even though the value is the same, 89% to 82%, right. So the difference is 7%. But if you look at this graph, its makes it looks like Michigan only half the number of people wear seatbelts compared to California. The way they did that is by breaking the graph at the bottom. So this only showing you values from 82 to 89 is to enough taking the intervals correctly. They broke this graph, so this one is misleading, okay.
So lesson to be learn is even though the graphs of if actually correct, this one and this one are misleading because they make you think that the profits grow faster or that the California residence are twice as likely to wear seatbelts as Michigan etc, when the difference is only 7%.
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