Introduction to descriptive statistics and central tendency. Ways to measure the average of a set: median, mean, mode
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Sal, you are outstanding, like your videos and get benefitted a lot. Regarding the one on which you spoke of Population and Sample Variance and lowering of the denominator for a better estimate of sample variance representing Population Variance, would you not look into the fact that the statistic would be valid only for representative samples. Would taking random samples also lead to big difference in sample and Population variance values?
The quality control department of Atherton Mills specifies that the mean net weight per package of cereal should not be less than 20 (μ=20) ounces. Experience has shown that the weights are approximately normally distributed with a standard deviation of 1.5 (σ=1.5) ounces. A random sample of 15 (n = 15) packages yields a mean weight of 19.5 (x̅=19.5) ounces. Is this sufficient evidence to indicate that true mean weight of the packages has decreased? Hint: (H0: μ≥20, HA: μ<20), Z=x-n, α=0.05
Thank you for providing free knowledge.
I came here from channel - Siraj Raval.
To learn Machine learning, he said we should know Maths, statistics and probability and he gave reference to your channel.
And love from India, specially from Mumbai.
For many years, my family and myself, have used your channel. I find myself here; yet again. Thank you. I am getting so close to graduating with my Psychology degree. To get a better understanding, you just know how to use proper word choice and I am grateful for that. Thank you so much!
Hey Sal, 'arithmetic' is an adjective in front of mean, and is thus pronounced ARithMEtik, not aRITHmeTIK, i.e. primary and secondary stress on 1st and 3rd syllables not 2nd and 4th. Thanks. It just kinda bugs me on a vid that is otherwise great.
Hello Mr. Salman Khan, I like your teaching style and your videos are very helpful. A small suggestion, you talk a lot about little things and that feels distractive, so it will be better if you stick to the main concept and decrease your intensity of using small talks in the videos.
I've never been good at the quantitative side of things. Now that I'm looking at grad school I'm worried about falling behind. Probably going to have to take stats in my last/second-to-last semester, and I need to keep my GPA up at the same time... Looks like I'm binging this series over the summer...
I love you man. When you explain math its like you're explaining a story or something. You don't explain procedures, you explain both procedure and reasons. And because you use accurate terms for every specific situation makes me understand the real meaning behind each word. Man you're one in a million
Thank you for helping me pass Elementary Algebra high school today. I WAS going to be in a non college credit remedial course. but not anymore. scored 61 on the 1st test(Accuplacer) and scored 88 today for my retake
This is an excellent series of videos. Very clear and informative, while including the viewers intuition.
I think however, that some ultra basic understanding of Philosophy of Science, will help everyone's motivation for learning statistics. You have to be kind of nerdy one, to really appreciate this math, but philosophers like Karl Popper has pointed out, that no matter how hard we try to measure something, we can actually never prove, that we will measure the same value the next time we try. Try to wiki "Popper Black Swan" for an excellent example.
This uncertainty in any science is perhaps the main reason why this is important stuff. It is kind of a, what Kuhn would call, mental paradigm shift, once you understand the meaning of all this, but it makes statistics a lot more interesting, than just learning the formulas.
Your explanation makes statistical concepts understandable and comprehensible. I used to have many fears and doubts in statistics...now I am more confident and enthusiastic to attempt to solve stats problems. Thank you Mr Khan, and god bless.
literally paying 5 grand a semester and free youtube videos teach me more. I'm taking a class right now called Vegetative Sampling Method and Design and my prof expects us to know statistics from day one, even though its not a prereq
What statistical test to use when the researcher likes to know whether
note taking has effect on students academic performance based on the
quantity of their achievements (whether they became honor students
etc.)? The basis for achievements are: How many times did they achieve
High Honor, Honor, Principals Lister, Top Student in class.
For real though my professor is so under qualified to be teaching this. She assumes too much in thinking her students understand everything she spits out as fast as possible then ends class early so she can go do whatever. She doesn't break anything down or explain things properly. She's a part timer and I don't think she realizes that a lot of us need this credit to graduate in the spring but here we are, barely passing or just below failing. Khan Academy should just do universal online courses for statistics and other math course. Better than literally any other institution that isn't a prestigious and highly recognized school like McGill, Harvard, Yale, etc. So thank you Khan Academy. You might just be the only reason I graduate and get this Stats credit. Paying all that tuition money just to teach myself by watching online videos by Khan... The education system is broken.
I believe they call it "Bimodal." Essentially, when considering mode, you can come to three conclusions. So if your set is 1123, the mode would be 1. If your set were 11223 it would be bimodal with the modes being 1 and 2. However, if your set were 112233 there would be no mode. So, you can have: 1 mode, bimodal, or no mode. Hope I explained it well!
OMG, I actually understood that!! I was even answering questions before he gave the answer. That was fun, I never thought I'd say that about stats. I find this impressive since the last stats class I took was back in '95. THANK YOU , Can't wait to watch the other videos.
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