Everyone. So today we've been given another scenario on asked a couple of questions about it. And so, just like with, I'm actually just going to write down all of the numbers that we've been given so I can help you identify which ones are important on which on. So we're told that the average birth weight I'm gonna put B two B for birth weight in the US is 3300 grams. And what were then told is that the average birth weight, um for babies off women living in poverty. Um, I'm just gonna write women impulsivity to be Why pay is 200 at Sorry, 2800 grams. And this is I'm literally reading through the paragraph. Justo, Sorry, Just let you know what I progress about. It's talking about the mean birth weight off babies and especially looking at the mean birth weight of babies who are born to women who live in poverty and so were given a bunch of different nation on the baby's birth weights. And so I'm initially we definitely have more numbers in this paragraph than we need. And so, in this first instance, I'm just trying to help you see which ones are important and which ones aren't. Which is why I'm writing all these numbers. And we're told that the standard deviation for this average here is 500 grams. Now, that doesn't necessarily mean that the every son of deviation for the average birth weight in the U. S. Is 500. It specifically says the standard deviation is for babies off, um, women in poverty. And then it's talking about how the hospital has looked at a new prenatal care program in the Hope Teoh improve the birth weight of babies born to women in poverty. And so they do this, uh, discourse. And then I take a sample and I take 25 randomly selected babies. So 25. And that's the number in our sample. And they take babies off women who live in poverty. Andi, they took part of program and the mean birth weight for those babies. So expo was 3000 and 75 grams. Now, the questions asking us, is there a significant improvement in the birth weight of babies born poor women? And we're told to use a significance level of no point naughty. Okay, so Obviously we have a one to many values here, and important thing to notice is that actually this value up here at the top the average birth weight for babies in the US isn't important to this question for us. We're only looking at babies who boards women in poverty. And so this is some context for the question. It's saying that women in poverty have a lower birth weight on average than the general in the US But in terms of this hypothesis test, we actually don't need this value. But all And so what we're gonna do is we're gonna use these values here. I'm gonna start doing hypothesis test. And to do that, we gotta start by using this handy. Formula two car codes that star so said style is equal to X for which we're told is 3000 and 75 minus mu, which were using 2800. And then we given 500 grams of standard deviation. Have a Rouen, which is route 25. So, people this NJ can't connect that you're gonna get out a value of 2.75 actually, what I should have done First of all, after we roll out, this number is we should have, um, were in high potties down. So what are our hope all season? This question Well, we're looking at one of this study has improved the birth way off babies born to women in poverty. And so no hypothesis is that it hasn't improved it and therefore that it would be in line with the average. So I know hypothesis. We told you to right here tells us that we reckon the population, I mean for the birth weight of babies born to women of poverty is 2800. And I offered about this. Is that actually this study? This course improved that the birth weight increased. And so now we have as that star value and we can use this to find a P value on RPI value for this which we confined using the tables or our calculators If you vote for this is no 0.0 Syria to nine eight on we given this significance level half, which is no point no to. And what we find is that this number is far smaller. They're not significant level. So what that means is because we have P is less than Alfa. We reject Haitian. We found significant evidence to suggest that this, uh, prenatal program improves on increases the that mean birth weight off babies born to women in poverty on because we I found it significant, um, improvement according to the note point not to level of significance, we can safely reject fictional. And so, in terms of answering the specific questions, I realized that this is, um, just a normal hypothesis test I've done here and were given in the textbook is in specific questions to answer. And so to start with what has to define the prouder, that's what I was talking about up here. When we're talking about which is important, what are we measuring? So what we're measuring just right away here is we're measuring the mean birth weight, and I'll write it properly rather than using my acronyms. Mean birth weight off babies phone that to women in poverty. And so that is what we're measuring it for. You could read that even though it's a little bit hard to right here. And so the normal tone of hypotheses we came up with right here and again. That's what mu is. This is just a wordy version of what Mu is were saying that the mean birth weight of babies born to women in poverty It's equal to 2800 always great in the 2300 when we're talking about specifying the hypothesis test criteria. What we're looking at is the conditions that we need in order for this and in order to start looking at a sample on the test. And so what we have to do is we have to assume no normality on what that means is we're assuming that the population off birth weights roughly follows a normal curve. And we can often assume this using something called the central limit their, um and so for use in central over there. Um, we have an is 36 on our standard deviation. Starting off the basics, reading the wrong news. Um, for this we have and is 25 Andi, Explore. Sorry. My expo, my dear Onda Ah, sigma is 500. And so we can use these to form standard error which helps us use the settlement there to issue normality. Now, today, sample evidence is the information we get from our sample. And so I thought, again, we given the any 25 I'm were given the Expo is 3750. So that's our sample evidence. And so when it's asking for their probably probability distribution information, that's what we calculate up here. That's said Star on RPI value values. And again, determining the results is what we did. Just hear. While he compared up, he value with a significance level and decided that the Coast P was less an Alfa. We can reject a channel, and so that's looking a bit closer at some of the specifics of the questions that arrest.