Master of Orion II: Battle at Antares/Summary of techs by level

The previous pages presented research costs as if they were exact and always the same. It's more complicated than that.
 * How research really works
 * Each research level has a set base cost, as shown previously and displayed in the game.
 * After the base cost has been paid, additional research points increase the chance of a "breakthrough", which causes the technology to actually be researched.
 * The game displays its estimate of the number of turns until a breakthrough in the research status box. This number can be high or low, as the exact timing is random.  Once the base cost is paid (and the research window displays 0 RP required), the percentage chance of a breakthrough on the next turn is also displayed in the research status box.  Note that this percentage includes the current turn's research, so may be altered by adjusting the amount of RP produced.
 * Once the base cost has been paid twice (e.g. Advanced Engineering after 160 RP), including the current turn's RP, the technology is guaranteed to be researched on the next turn. At this point, the Research Status box will display 100%.  It's not clear whether this number can be rounded up to 100%, so there may be a small chance that the research not complete when 100% is displayed, as the total RP may be just short of twice the base cost.
 * When you begin researching a technology, the game will always estimate at least two turns of research, even if you have enough RP to guarantee an immediate breakthrough.
 * When 100% is displayed, you can safely transfer scientists to other jobs, provided the probability does not drop below 100%. You may wish to leave one extra scientist, in case rounding has occurred.
 * A better method is to use more expensive technology to determine how many RP have been spent, and calculate the exact number necessary to guarantee a breakthrough. If you are researching Artificial Life, you need to spend 9000 RP total (4500 base cost, x2).  If you also have access to Temporal Physics (15000 RP) and it displays a cost of 7520 RP, you know that you have spent 7480 RP (15000 - 7520), and that you need to spend another 1520 RP (9000 - 7480) this turn to guarantee research.  Any excess RP is completely wasted.
 * If immediate research is not necessary, scientists may be transferred to other jobs as soon as the breakthrough chance reaches an acceptable value. If you have a 50% chance of breakthrough this turn and do not get it, you will still have at least a 50% chance of breakthrough next turn, even if you generate 0 RP.  You therefore have an 87.5% chance of a breakthrough in the next three turns (and over 99.9% in the next ten turns) with no additional RP investment.

The value of scientists in other jobs is dependent on the circumstances. If your race is Tolerant or the colony contains production buildings, you could make your ex-scientists produce Trade Goods - you'll need the money some time, possibly to finance an invasion campaign. Otherwise, it may not be useful to move all your scientists into industrial production as a lot of it will be wasted by pollution. Research colonies tend to have high populations, so Housing is not efficient there, but may still be useful if it produces an extra citizen. Farming may be the best general alternative, as the surplus food will increase your income, and may allow you to reassign farmers to production on other planets.

In any case, however, reclaimed >100% scientists represent free effort, provided you remember to put them back to work after the breakthrough.

Summary of techs and research costs
Eight pages of tech details is a lot to remember, so this page tries to summarise the most useful points for each level, excluding the starting and Hyper-advanced techs:
 * Name of each tech level (e.g. "Astro Biology").
 * Names of the techs in that level.
 * The most usual choice(s) for non-Creative empires.
 * Number of RPs needed to research each level.
 * Cumulative number of RPs needed to research each level from a Pre-Warp start. This will show how many RPS in total you need in order to get from your current position to some tech you really want - subtract the desired tech's cumulative RPs from your current level's cumulative RPs; then you compare the result with your current research output (bottom right of the Galaxy map and Colony List screens). You may then decide to research and build some more research buildings first.

Remember that the "Usual non-Creative choices" are only a guide:
 * Choices you make in other tech subjects may makes other choices useful.
 * You must adapt to what your opponents are doing.