Raven's Simplicist Guide to Economics for newbie Space players

As a result of this I decided to write a basic guide to Space' economics with a try to keep it simple as possible which means least-PG-oriented as possible

some player wrote : 
Credits Total: 2,153
Total Population: 76,288,217
Mining Total: 820
Production Total: 1,274

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one mega holds 10000 pop
one facility (facs, labs, mines) can give jobs for 5000 pop

So one megapoli can support two facilities. Which means 1 mega + 2 facilities = 3 land used. That means you need to build around 33% megas min./max. in total if you want to put up more facilities. Often you do simple computation: free land/3 + leftovers = number of megas. So 100/3 = 33.33, so you will put up mostly 34 megas rest facilities. If you need pop and growth you will however go for 50% megas/50% facilities setup but you do have enough pop just check if you lack facilities.

Each facility will produce 10 of it's resource per day. Each tech gives +.4 per day. For labs: +0.5 per day. Ore concentration lowers output for mines: so 50% means 50% of total possible output.

As for when to build Ore Mines:

Look at your max. possible toag market discount in your alliance. You see we have 32% max. What does this mean ?
You buy ore and production 32% cheaper.
Base price of ore is 4.4 and of prod it is 2.9. 
Your final purchase price is: 2.992 for ore and 1.972 for prod. 
Your selling price is always max. discount (40%, like if you have a Toag): 2.64 for ore, 1.74 for prod.

Now let's check, a mine becomes inefficient if it produces less ore THAN if you would just have the amount of mines replaced by factories and have the output traded into ore ! Remember you want to have prod-to-ore exchange inefficient, so you compute when it becomes efficient and that is when you get more ore for prod than if produced on that planet.

For instance: 80% ore and you have lvl12 ore and lvl15 production:

So a mine would produce 0.8*(10 + 12 * .4) = 0.8 * (14.8) = 11.84 ore per day.
A factory would produce 10 + 15 * .4 = 16 prod per day

Traded into ore it would mean: (16 * 1.74)/2.992 = 9.3 ore per day, since 11.82 > 9.3 it means our ore mine is efficient.

Let's take a second example 50% ore, same techs like above:

So a mine would produce 0.5 * 14.8 = 7.4 ore per day
A factory would produce 16 prod or 9.3 ore per day
As you can see at this planet you should consider factories instead of mines.

We can now easily compute the point when a mine becomes inefficient here, it does when mine produces less than 9.3 ore per day ! When does it do it ?

9.3 = 14.8 * x, x = 62.8%, so simple said: When your planets have <63% ore you can scrap mines and build factories there IF your tech levels are like described above.

Word of advise: Try to maintain equal tech levels. Why ? Not only because each level reduces the cost of a ship by 1% (prod lowers prod costs, ore lowers ore costs) but also because you can compute the ore concentration where mines become inefficient alot better:

Imagine both lvl17 ore and prod AND you have 32% market discount:

Ore mine would produce (at 100%):
10 + .4 * 17 = 16.8 ore
Factory would produce:
10 + .4 * 17 = 16.8 prod, trade that into ore:
(16.8 * 1.74)/2.992 = 9.77 ore
9.77 ore/16.8 ore = 58% , so it will become inefficient <59%

Generally you aim for equal techs to have it computed easier. When you see a planet look at its size first: 

Is it big ? (>950 land);
     if yes: Is the ore concentration so that it is efficient to build mines ?;
           if yes: then build mines. 
     if no: then check if you need population (growth is too low and you need to expand faster), 
             remember you need 2.5M pop for one colony to support, so the number of megas should be somewhat divided by 2.5 at least result into 4 colonies at least
             if you do not need more pop then check if you need research or production or both and build labs and/or facs
if it's a small planet then check for research or production needs.

Only make in absolute case of emergency smaller planets to pop planets but prefer a 50%/50% setup in this case.

Another topic: Megapolis. They serve two purposes. Holding population and generating credits by paid rents and taxes.
I will go for the latter aspect, generally population not assigned to any job is called unemployed. No jobs at all means 100% unemployment.
Depending on the ratio unemployed : total population a megapoli will generate a certain amount base credits but minimum 1 credit per day.
Economics tech will increase it by +0.5 credits per day per tech level. Toags get +20% added to the final amount generated.

Last topic: How much mines to build ? That depends: if you prefer strip mining then you will need HIGH ore tech level because it lowers the drop rate of ore and/or being Shy'dow. Then you can build all-mines on that planet. If you go for balanced set up (facs + mines per planet) then I would say go for 400 - 450 mines max. or alternatively get my OreCalc from my site (http://www.8ung.at/darkpetrel).

As for research: Try to get it that high so that you do not exceed 12 hours max. IF possible (in late game it is sometimes not possible), you may adjust it to your needs later.
When you are done with all needed techs in late game you will probably replace all labs anyway by factories or mines.

Note, after you got a hang on this quite simple issue you may going into finetuning your econ, replacing obsolete mines by factories, adding/removing megapolis etc.

Your Homeworld and beginning phase: Don't scrap your labs, I can't say it often enough the idea to scrap your starter labs is only for advanced players who got extremely lucky in finding planets. Your megapolis and your 100% hab justify a combined development: add megas, add mines so that the final amount of mines on that planet will be 450 and put the rest into factories.
Put none into labs, your first 2 - 3 colonies after your homeworld will remain completely lab-less too until you got some more experience in the game to create your own starting schemes.

Advanced topic 'colonization' and colony development:

This aspect is viewed from peace times not war times. So consider anything said as peace time development.
What to colonize ? Generally your goal will be expansion so your planets of choice will be border planets and your choice will be ore-rich planets with good habitability.
Don't hesitate to trade bad hab planets away to allies !
Keep in mind that your economy produces less the worse the hab is on that planet including slower pop growth.
After colonization do not wait until the planet has reached 100% habitability, spend your resources whenever you have to spare some for development.
Keep an eye on efficiency: population assigned to jobs, if facilities got less than 70% of the population needed or in short are less than 70% efficient then pause the queue,
check capacity which is determined by the current population inhabiting your megapolis, say you have 10 megapolis and only 5000 population megapolis are at 50% capacity, if capacity is less than 50% then population grows fastest, if you can add megapolis in this case to maintain the best growth rate possible but if you can't add more megapolis then have the queue halted until efficiency goes up again.
Some say efficiency management doesn't pay off, some say it does, an iron rule is that population growth is more important pure facility development, thus efficiency development is efficient during times when your race's population growth rate is low (important for Sirnef and Oomari players).

If you found a good hab planet (>=70%) then you will most likely set it up like this: 1 scanner, 40 bioformers and rest megapolis.
About the bioformers: it is assumed you have nanotech lvl1, you can safely reduce the amount by 2 per each nanotech level over level 1 or you can stick to the same number of bioformers resulting in halving the time at lvl 11.
After colonization you may build up to 200 megapolis. And then add about 100 - 150 facilities and then you will build the rest of the megas and add the rest of the facilities.
 
If you found an average hab planet (>=55% && <70%) then you will most likely set it up like this: 1 scanner, 60 bioformers and rest megapolis.
After colonization you may build up all megapolis first and then add all facilities needed, or you will go traditional 200 megapolis first.

If you found an average hab planet (<55%) then you will most likely set it up like this: 1 scanner, 80 bioformers and rest megapolis.
After colonization you will build up all megapolis first as your growth rate on that planet is lowered by the bad hab.

Side note: Some people say it doesn't matter later if you build megas first or not, in early game when you need credits to pay your upkeep it is important.
Later in any case it's safe to invest into development of facilities by combined build up of megapolis and facilities after your reached 82% hab or higher.

Final comments:

I expect a few "yada yada" comments from the elite players here like "Raven your guide shows me what n00b you are !" but that's okay considering none of them would ever be willing to reveal their secret in a public guide like this.:P
I am mostly too lazy anyway to follow anything described above so are many players, so don't expect any player even veteran to play like a robot.
I want to conclude this guide by a famous quote from Sir Winston Churchill: "Success is the ability to go from one failure to another with no loss of enthusiasm."