Estimate the number of groups on Facebook

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Estimate the number of groups on Facebook

With approximately 2.6 billion users on Meta (Facebook) and each person is a part of some group, how many groups might be on Meta (Facebook)?

Help me solve this guesstimate

Asked at Meta (Facebook) over a year ago

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rahul_g · Answer 1 · 2021-04-13T14:29:51+0000

Clarification

When you say each person is part of some group Im assuming you're referring to the possibility but not that as a fact, so I'd like to correct the scope of the problem to how many FB groups are there assuming each person can belong to a potential group.

Also the goal here is to count the number of groups, it may or may not have members/we are not concerned with how many members exist on FB.

When we say groups you want total groups that exist, we aren't concern with active or inactive status of the group

Let me spend a minute on groups, a group has 2 major components: Creator and consumer
- The creator is usually the admin as well and a group can have multiple admins
- A group creator can create multiple groups
usually the creator - consumer ratio is 1%
so I can assume 1% of users are creators however that applies to posts, I think in case groups this number would be similar
I'll take 1% as that number
- Groups once created continue to exist,a creator may create 1 group per year for 2 years and hence actually contribute 2 groups, we need to account for this
- We can account for this by factoring in group ownership rate
So total number of groups = number of creators x average groups per group creator which looks something like
Number of creators = 1% of 2.6 billion or 2600 million = 26 Million

Creator type	Frequency + weight avg per creator	Share	groups created( Millions)	Comments
one timer	once in lifetime	50%	13 Million	Highest share
Low frequency creator	2- 4 groups per creator 2.5 groups/creator	20%	13 million
Medium frequency creator	5- 10 groups per creator 6 groups/creator	10%	15.6 Million
High frequency creator	10 to 20 groups per creator 13 groups per creator	8%	~27 Million
Very high frequency creator	20+ groups per creator 25 per creator	2%	13 million

That totals upto 81.6 Million groups, at first glance that seems a bit low - I think I have undersestiamted the creation rate since a person has a lifetime to create a group so i need to factor that in and 1% applies to a yearly rate so given the decade+ existence of FB group creators would 4-5x of the 1% rate over that period so I'll take a 4x multiplier and thats about 326 million

however some of created groups would also be deleted during the period, assuming that number to be about about 10% so that would be about 295 million groups

Vishal Shah · Answer 2 · 2021-03-08T05:30:30+0000

I: Can I narrow the scope to groups created in India by people of India living in India since I already calculated # of people in India who have FB account earlier? It would make the answer quicker considering I plan to use that estimate to dereive # of groups on FB for Indian population.

Interviewer: sure.

I: Ok first I plan to estimate how many Indian population have FB accounts. Then, I will estimate how many actually use FB since those who don't use FB won't create groups. That will then help me estimate how many groups might be created. Can we take that approach?

Interviewer: Sure. I don't see anything wrong with that approach.

I: Ok great. And I assume we are not attemping to wnat to narrow it down to groups created using what device such as cell phone vs. laptop vs desktop vs tablet. Correct?

Interviewer: upto you.

I: No let's keep it generic for this exercise.

I: True. Ok, India's population is 1.3 billion.

Let's assume 30% of India's population doesn't have internet access considering it being a developing country infrastrucutre is still poor in many parts and poverty level in india. So that brings us to 910 million with internet access.

Out of those, 20% are little kids, 20% are old people and rest 60% are youngsters and young adults. Those 40% are not likely to have FB account so let's exclude those. That means those other 60% who could have FB accounts = 546 million. From those 546 million, let's assume there are about 20% who don't have FB account due to people being concered about privacy so much. So 80% who would have a FB account = 436.8 million.

I think it's safe to assume that there are about 40% who don't use FB though they have FB account. That means 60% = 262 million.

Also, of these, there are significant population who actually don't create a group of their own but look for groups already created to join them. So 20% who would create groups = 52.4 million people creating groups. I say only 20% since that 20% creating groups and possibly easily support the rest 80% of the population.

Of those, let's assume:

40% creates 1 group per year = 21 million

30% creates 2 groups per year = x * 2 = 32 billion

20% creates 3 groups per year = 10.5 million * 3 = 31.5 million

10% creates 4 groups per year = 5.24 million * 4 = 21 million

So that's about 105.5 million groups.

That seems quite high to me considering we were just looking at groups created in India. Where I may have gone wrong is estimating % of people who create multiple groups. But even then, I get a sense that the number might just be too high. So then, it could very well be % of people who create groups is much lower than expected. I don't think it could be anything other than that considering that I do believe Indian population who have FB account is pretty accurate.