Hi
My name is Andreas Tilevik. With this channel, I thought that I could share my video lectures from my courses in statistics and systems biology at the University of Skövde, Sweden. Note that the target group is mainly with a non-mathematical background. The videos will be published in a logical order at:
www.tilestats.com
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thanks for this benefical video. Just to clarify: in reality, we can never be certain whether or not the Ho is true, as we seldom deal with a true population and mostly deal with samples, correct? Your example in this video assumes that we know the entire population statistics, right?
Yes, in reality we do not know if H0 is true or false unless we have measured the whole population. Yes, the video assumes that we know the population, which is possible with computer simulations.
@@tilestats Thank you. And as a follow up, we can never be sure if we have committed a type I or II error since we never know the true population parameters, right? The most we can do is minimize the chances of committing both errors, right?
True
Despite of negative coefficient value/ taller person has lower bp/heavier person has high bp. This is not clear to me. I also faced such type of result in CCA but cant interpret the result. Would anyone plz define me.
Thank you!
This video explains in detail about the concepts and the same time takes away apprehension ,skepticism whether we will ever be able to understand the basics of it.. Hats off to the content creator.. i have been trying for months to recollect regarding statistical test but could not find means to do it. Thanks a lot
thank you so much! very helpful!
Hello, I loved your video, it helped me understand and carry out this analysis in R. I would like to ask you a question! If I have a model with 3 parameters, like the Chapman-Richards model, how would I place the distribution of the parameters in R, in terms of its fixed and random order?
How to calculate score from to matrix
best videos for classification on youtube. thank you!
phenomenal explanations!very intuitive and understandable to a beginner. once again, thanks a million times!
Extraordinary!!! Fantastic!!! Bravo!!! Thank you,professor!🥰🥰🥰
Best stat lessons on YT
Much thanks for this video
Best video I've seen on the subject, well done!
love it thank u❤
This has to be the best video I have seen in my years of trying to understand this.
Nice video. I have a question about using logistic regression with low prevalence (23:25): does NPV decrease due to so many false negatives? On the contrary, we saw the opposite in the example of video about PPV and NPV: FN decrease and FP increase. Maybe we need to use a cutoff value lower than 0.5?
Nice video. I have a question about using logistic regression with low prevalence (23:25): does NPV decrease, due to so many false negatives? However, in the example of the video dedicated to PPV and NPV, false negatives decrease and false positives increase with low prevalence
Do you mean low prevalence in the sample or in the population? With a low prevalence in the sample, you can adjust for this by changing the cutoff value.
@@tilestats ok, i'm agree. Is PPV calcolated considering prevalence in population? or in the sample? In last case, should I take into account the prevalence of the population when i'm sampling?
@@tilestats Please, tell me if I'm right: even considering a low prevalence in the population, I take a sample with a prevalence of 50% and I set the cutoff value that maximizes accuracy. Finally, I calculate PPV considering the prevalence in the population.
@giovannibrufani3603 yes, sounds right to me. I would also try to calculate the accuracy based on a test data set that I explain in the video about validation.
@@tilestats Sure. I'm not missing any videos in the playlist. Thank you very much for your work and for clarifyng my doubt!!!
00:03 K-means clustering divides data into k clusters. 01:19 Determining the value of k is essential for k-means clustering 02:41 k-means clustering assigns data points to the nearest centroid and updates centroid positions 04:11 Clusters shifting based on proximity to centroids 05:36 Measuring cluster performance with within-cluster sum of squares 06:58 Choosing the best clustering output based on within cluster sum of squares. 08:22 Optimal value of k in k-means clustering 09:39 The optimal number of clusters for the example data is 3.
At 08:20 I wonder how will you normalize the eigenvector if there were three rows in the vector instead of two?
Just extend the equation by the third value. You sum the three squared values and then take the square root of the sum.
thank you so much sir this videos are really helpful🎉🎉
Fantastic explanation👑👑👑, Thank you very much.
does all scenarios probability form the sigmoid curve when plotted ?
Why do you change the example midway? You didn't explain how you calculated the equations.
I really Loved your explanation thank you so much, but I did't understand how C*E will affect the margin ?? I know why 2/||W|| is affecting the margine, but C*E is not clear for me, please answer me if you see this.
Because you want to avoid misclassification (C*epsilon), that will affect the optimal values of A and B (w) to minimize the error function.
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can you make this available for purchase with the other nonlinear regression books?
Sure I have now put together one product with 4 optimization methods.
video lecture on Eigenvector and Eigenvalues mentioned at 05:31 can be found at kzread.info/dash/bejne/a3eIksynldCaprA.html
Best tutorial ever on Eigenvectors and Eigenvalues. Thanks
please provide link or the full title of the video you are referring to as next lecture at 11:55.
please provide link when you are referring to your previous video at 06:04 . overall I liked the way you explain difficult concepts so easily.
Sir, how much of statistics is required for the business analytics program?
Hello sir make video on LSTM as well thank you.
It seemed to me that the Spearman's rank correlation has no downsides in comparison to the Person correlation test. Are there cases where the Pearson correlation test would be used?
Great thank you. Would you please make also a video on Duncans MRT post-hoc test?
I can't believe the concept can be explained this simply! Nice one! You have a new subscriber. I honestly think it's criminal that something this simple is made overly convoluted by other individuals.
Hey from where the dataset has been taken? Important and needed urgently
It is simulated data based on an exponential model.
Sir, how the concept of euclidean and mahalanobis distance are related to the field of business analytics?
Good video thankyou🎉
You have explained it better than a PhD. Stay blessed.
And you my friend, you are the real hero
I have one question: this type of graph at 1:25 to visualize the effect of the clusters on the regression line is very helpful. But what if we have multiple independent variables. How can we visualize the regression line across the clusters?
Your explanations are very clear. Thank you so much
very comprehensive explainnation. thank you
Thank you sir for this video
Basic example but good ! thanks :)
Amazing explanation!
Thank you for the good video! One question I have is, how to draw the ellipse shown in 2:40? As far as I know, we usually use 95% of a confidence ellipse (p = 0.05). Is it obtained by the value of the Hotelling's T-square test statistic? or F-statistic?
It can be based on the T2 value in combination with the eigenvalues and eigenvectors of the covariance matrix, similar to how an ellipse is drawn based on the Mahalanobis distance. kzread.info/dash/bejne/qoycrtihlaisZ9I.html
@@tilestats Thank you for your answer!
it's not clear at min 7:47 why the loadings, and not the scores , represent the coordinates of the data points in the PC1-PC2 plane
Thank you for the video!
great