Making a prediction based on results from a single experiment
About this video
Renato serves a tennis ball 12 times: 10 land in the service box and 2 land outside. Based on these results, landing in looks more likely on his next serve, though a small sample can't tell us for sure.
You'll be able to
- use results from an experiment to predict a likely outcome.
- explain why a prediction from a small set of results might be wrong.
Key words
- outcome
- One possible result of an experiment, like a serve landing in or out.
- sample
- A set of results we have collected and use to make a guess about what usually happens.
- likely
- Expected to happen more often than not.
Transcript
- [Instructor] We're told that Renato is practicing his tennis serve. He serves the ball 12 times and records whether each serve lands in the service box or outside the service box. So, he got in, in, in, outside, in, in, in, in, in. Bunch of ins and outs and in.
Based on these results, what is Renato most likely to get on his next serve? So, pause this video, have a go at that before we do this together. Okay, So let's just look at the data we have so far. We have one, two, three, four, five, six, seven, eight, nine, 10.
So, we have 10 ins and we have two outs. So, two outs. So, in the future, we're gonna talk about how you can do this a little bit more exactly and you can maybe do a little bit of math to say, "Okay, if this is a sample of what's possible, how can you calculate that?"
But in this video, we're just thinking about it a little bit intuitively that based on what we see so far, we don't know for sure, but it looks like it's more likely to get an in than an out. So, let's see which of these have that. The serve lands, so what is most likely to get on his the next serve?
Lands outside. Well, that data definitely does not back it up. It looks like two out of the 12 were out, so it's definitely not most likely to get an out on the next serve. I would say it's more likely that we land inside the service box based on what I have seen so far.
We cannot predict this information. We might not know exactly what the probability is yet, and there's ways that we're going to estimate that in the future. But just based on the information we have, it does look like, at least so far, that ins are more likely.
Now, it just might just be happenchance. Maybe they're equally likely. Maybe even outside is more likely, but we just happen to get a bunch of ins in a row. That's always a little bit of the asterisk, a little bit of the question mark when you're dealing with probability and statistics.
But based on the information we have so far, it does look like in is going to be more likely than out in the next serve.
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