Homework 7 FAQ

Q1: Should I leave the printed copies of homework 6 and 7 in your box thing at the cogsci building? Otherwise let
me know how I should get you it you.

Q2: I have run into a problem on the take home final and i was hoping that
you could point me in the right direction. The problem i ran into is with
2.4.3 and the artificial neural networks. I am trying to run the
problem3.m file and i keep getting an error coming up. the error in
matlab states:
??? Undefined function or method 'newff' for input arguments of type 'cell'.

Error in ==> problem3 at 18
net = newff([0 2],[3 1],{'tansig' 'purelin'});

I am not sure what to do now, I have a student version of Matlab so i do
not have the neural network tool box, and I am unclear on the instructions
in the assignment for if you do not have acess to the neural network tool
box.

Q3: I have a question about the neural networks modeling question. I am having
a hard time figuring out what the four specific methods are. Do you think
you could point me in the direction of the lecture that this was covered
in. I would really appreciate it.

Q4: I'm working on the takehome final right now, on Problem 2.2.3, where it asks to calculate the means and standard deviations. Then, it asks to calculate the covariance of these means and standard deviations. When I calculate the covariance of the means and the covariance of the standard deviations, I get zero. Is that right?

Q5: I

Q6: I

Q7: F

Q8: I

Q9: E

Q10: I

Q11: W

Q12: I

Q13: H

A1: I put a box in csb115 next to the printer, please turn both homeworks in there if you have not turned it in to Alex directly.

A2: In the case of not having the neural network toolbox I gave you the results of the calculation in the .mat file - that's the Y.  Read what the question asks carefully.  You essentially just need to plot the results - again read the question carefully.

A3: last lecture and first lecture - 4 stages of modeling and data analysis.

A4: If you mean the takehome, where is the question about covariance?

2.2.4
In general, what does the concept of the mean tell us about our data (4 points)? What 
does the concept of the standard deviation tell us (4 points)? In this specific instance, what 
is the numerical relationship between the value of the mean of sub ject1 vs. sub ject2, and 
what is the numerical relationship between the value of the standard deviation of sub ject1 
vs. sub ject2 (2 points)? (Hint - calculate and compare) 

I just ask for the numerical relationship (which is bigger?  Is there some proportion you can find?  like, divide one by the other and see what you get - ie mean1/mean2 = ? )

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