Hubs & Authorities

Big Data Analytics
For more: www.anuradhabha...

[@deepeshgolani1]

Thank you maam! We still miss you from my diploma days

[@nishantaridamankumar9376]

Program implementing the above algorithm: import numpy as np NAMING_ARRAY = [] k = int(input()) nodes = int(input()) adjacency = [] strength_adjacency = nodes*nodes for i in range(strength_adjacency): if i < nodes: NAMING_ARRAY.append(f"N{i+1}") adjacency.append(int(input())) A = np.array(adjacency) A.shape = (nodes, nodes) A_T = np.transpose(A.copy()) u = np.ones((nodes, 1)) v = np.matmul(A_T, u) u = np.matmul(A, v) n = 1 while k >= n: print() print("ITERATION NO: ", n) hub = u.copy().flatten() hub_normalizer = 1/sum(np.square(hub))**0.5 authority = v.copy().flatten() authority_normalizer = 1/sum(np.square(authority))**0.5 print("Node\tHub Scores\tAuthority Scores") for i in range(0, nodes): print(f"{NAMING_ARRAY[i]}\t{round(hub[i], 3)}\t\t{round(authority[i], 3)}") sorted_hubs = sorted(zip(NAMING_ARRAY, hub), key=lambda x : x[1], reverse=True) sorted_authorities = sorted(zip(NAMING_ARRAY, authority), key=lambda x : x[1], reverse=True) print() print("HUB:", end=" ") is_a_tie = False for node, _ in sorted_hubs: if np.count_nonzero(hub == _) > 1: is_a_tie = True print(node, end=" ") if is_a_tie: print("{Tie}") else: print() print("AUTHORITY:", end=" ") is_a_tie = False for node, _ in sorted_authorities: if np.count_nonzero(authority == _) > 1: is_a_tie = True print(node, end=" ") if is_a_tie: print("{Tie}") v = v*authority_normalizer u = u*hub_normalizer n += 1 print() # 3

[@architlatkar2503]

for each iteration of k, we are simply taking unit vectors so it would naturally come the same in 2 iterations. So how is it useful? In some other cases such as page rank algorithm, i saw that the ranks converge to some values over several iterations, but here its not the case. Could you clear this doubt please?

[@hamzamaqsood1]

Its probably the wrong way.. for k=2, we get updated hub vectors by multiplying Ateanspose with previous Hub vector

[@rhysparsons2474]

This is good up to a point. To calculate the next iteration, it isn't enough just to re-normalise the values. You have to re-calculate the authorities from the previous iteration's hubs; update the hubs from that; then normalise. For k=2, the numbers should look quite different. See en.wikipedia.org/wiki/HITS_algorithm#Pseudocode for pseudocode for doing the same thing.

[@amur_]

Yeah, I was wondering the same thing. Looks like what she's done here isn't right.

[@techinfo6598]

thanx a lot mam., your teaching was so useful....

[@whatsaappstatus6452]

You explain every topic very easy and perfect 💯🤝thanks

[@cbh4678]

Thanks maam. I think there are some doubtful figures under K = 2. What I mean is that, during calculating authority score under K = 2 , N1 and N2 received different hub socres (respectively 0.445 from N3, 0.623 from N1). However you count both as same figures. This is why I am confused....

[@balasahebgadekar425]

Madam,I am not getting what is wigen factor,why it takes and what is its importance.Then why you take damping factor as 0.8, .What are the restrictions on Matrix. Is any special type of matrices or not

[@TheTerribleDreamer]

This is a very helpful video, thank you

[@muhammadnaveed5056]

waaaoo mam u r great teacher in world u make it very simple for me.

[@doyeldesarkar2276]

Hello mam, if you can upload a video on Latent semantic Indexing it will be great.. Looking forward.

[@parttimedude5440]

Thank You, Ma'am!

[@ganeshvadcar8098]

Wow, explanation made so simple and easy to understand

[@AnuradhaBhatia]

Ganesh Vadcar Thank you

[@0625faith]

thank you sooo much. It helps me a lot

[@amanchoudhary4547]

Awesome tutorial thanks ma'am

[@parthgulati4914]

we are dividing all the ranks by the same value so won't they remain the same, no matter how many iterations it takes?

[@shivakumar-fq1mc]

we have to multiply A Transpose with new hub weights to get new authority vector

[@zeetennayak1056]

mam your topic is HITS Algorithm for BIg data analytics but through out the video you have discuss about how to calculate hub and authority ranking. i dont find anything related to Big data analytics. HITS algorithm for ranking would be better.

[@blueguy5588]

Extremely helpful, thank you!

[@amarimuthu]

Hi Can you please make a video with an example for "Dynamic time warping" for Time series . I just could find any good resources on KZbin. Thanks.

[@KarthikBalan27]

Thank You Mam. Best explanation.

[@VirenJoshiOfficial]

In hubs and authorities In 2nd iteration are we suppose to use normalised value or normal values of h & a ?

[@AnuradhaBhatia]

Normal

[@sibinthomas9681]

No fake Accent. Crisp to the point explanation. Thanks a lot!!

[@parshvajain4556]

She still has to learn a lot from you to be where you are right now.

[@adarshmahto5645]

Hello maam your videos really very helped to us .. thank you for making these videos :) i have little confusion at @4:02 where if in-degree is 4 than outdegree will be 0 but u were mention as 1 . for ( node 4 )

[@AnuradhaBhatia]

Hi, The out degree is 1, as the node points to itself.

[@adarshmahto5645]

Thank you :)

[@AnuradhaBhatia]

Best of Luck.

[@adarshmahto5645]

Thank you :) ppr was good :) maam plz upload DWM videos :)

[@AnuradhaBhatia]

Good. Sure will do.

[@leanderpereira5257]

What about spider traps

[@nikhildange123]

If k is not mention in the question then can we assume as k=1?

[@hamzabilal6465]

Wow aapnay bohat acchay say samjhaya hai ayr aik hamaray sir jinko sirf bhaagnay ki jaldi rehti hai 😡😡😡 thanks a lot

[@grinalpatel1012]

Superb mam …thanks alot

[@aswani4402]

very nice explanation mam , thank you

[@arnavsharma7414]

Thank you so much Ma'am much appreciated !

[@AnuradhaBhatia]

Thank you

[@abhishekhawale6052]

Mam in exams they given a diagram to find hubs and authority where there are 7 edges so how can we consider 7*7 matrix

[@AnuradhaBhatia]

yes

[@abhishekhawale6052]

So answer will be much more lengthy than this na?

[@AnuradhaBhatia]

yes.. can you send me the diagram.

[@saurabhsingh8996]

Would have been a great video. if question and use of variables were shown in a better way

[@kunalborge5474]

yes it was because of you my papar was damn easy maam greatwork..

[@jayeshchindarkar]

thank u maam....ur videos of BDA n CSM helped us a lot in our exams

[@AnuradhaBhatia]

Thank you so very much.

[@divyasampathirao7306]

mam was the intial hub vector 'u' is same for all the given graphs?

[@AnuradhaBhatia]

Divya Sampathirao yes

[@divyasampathirao7306]

@@AnuradhaBhatia mam tq so much ....this video helped me a lot

[@siddhiipte876]

what is k in adjacency matrix?

[@ganeshvadcar8098]

is it necessary to have Adjacency matrix to solve this problem? but ma'm the matrix that you have considered do not have diag elements "0" so I am confused here. please clear my doubt

[@AnuradhaBhatia]

Ganesh Vadcar kindly mail ur doubt..go on to the website and post a query please

[@ganeshvadcar8098]

yes, I have done that, thank you

[@rashijain4207]

Nice Explanation mam..Please can u upload video on k-mediods with example

[@AnuradhaBhatia]

Rashi Jain ok..will put

[@korkorkotey-afutu8637]

youre a great teacher :)

[@AnuradhaBhatia]

Korkor Kotey-Afutu Thanks

[@mehtabahmed5725]

i want to ask some other question regarding the information retrieval techniques kindly advise me from which forum i can join and able to ask the questions? w8ng for reply

[@AnuradhaBhatia]

Mehtab Ahmed Hello, What queries you have regarding Information Retrieval, kindly let me know. Regards

[@mehtabahmed5725]

Hello Madam

[@mehtabahmed5725]

I have many quetion but this time i want to ask Is page ranking query dependent? What is Faign Algorithm

[@rahulbharsadiya2897]

what is the hadoop architecture?,is it the same HDFS ?,plz reply fast.thanks in advance

[@AnuradhaBhatia]

Rahul Bharsadiya yes...it is Hadoop Distributed File System..

[@AnuradhaBhatia]

Rahul Bharsadiya Refer to my notes on my site for Big Data

[@AnuradhaBhatia]

Rahul Bharsadiya all the best

[@rahulbharsadiya2897]

Thanks for your videos, support and for sure the notes ,thanks for good wishes

[@AnuradhaBhatia]

You are always welcome. You are from which college? Any help please feel free to contact.

[@marcomarkproductions]

what is 'k'

[@AnuradhaBhatia]

Step count in algorithm implementation. A k-step application of the Hub-Authority algorithm entails applying for k times first the Authority Update Rule and then the Hub Update Rule.

[@kingleomessi9707]

Mam can u teach friends of friends algorithm

[@kunalborge5474]

Thank u a ton....maam

[@AnuradhaBhatia]

Kunal Borge Thank you..

[@keerthu6022]

Thank u mam😍

[@mehtabahmed5725]

thx alot madam

[@mansingraomore4385]

Really helpful

[@AnuradhaBhatia]

Mansingrao More Thanks

[@hemanthkumargundumilli]

Please share the ppt madam

[@namansingh7721]

How can you normalize already normalized vectors, I guess each time we got to multiply by matrix but you are simply normalizing again so no matter what answer won't change. sorry to say but I think wrong concept

[@rawmusicbynm3540]

the video is wrong after k=2

[@gayuravi2812]

Mam can u explain fuzzy system

[@AnuradhaBhatia]

gayu ravi Sure..by when do you need it

[@myworldAI]

6 star video

[@abid_dasurkar]

BDA k liye kon aaya hai ??😂

[@mitaleeb6362]

Thanks a lot!! You are the savior. :)