If there are no improvements, current production is sabotaged.

Trying to sabotage a particular improvement is more risky than just trying to sabotage any thing; and some improvements such as city walls, coastal fortress, SDI
are more risky than others.

Once built a wonder can NOt be sabotaged or sold; only perhaps obsoleted or certainly irretrievably lost if the city is destroyed.

The probability of success is higher with a spy than a diplomat and higher still with a veteran spy.

The probability of success is much reduced if the city has a spy to catch your spy.

The message about the AI being suspicious only comes when a spy attempts to steal tech more than once from the same place. (Diplos can never steal twice fron the same city) Repeated sabotage in the same location does not seem to reduce your chances of success.

-----------

SG (2)

Military units inside the city do not help to hinder sabotage.

And yes dips do sometimes foil the steal tech attempt. I have seen it happen lots of times.
Civ2 manual: It says "each dips has a 20% chance to twart steal tech, spies 40%, vet spies 60%, and the effect is cumulative in the effort to do this. But I do not think that having 5 dips in a city will prevent stealing of a tech from it as it says regarding the cumulative effect.

the other cities each had 5 dips and anywhere from the 1st try to maybe 8 tries before a tech was stolen.

But, it would be such a loss of dips to steal against such a counterespionage defense that it may be too impractical. A player would need a bunch of dips ready, and unless they were on a boat, would be sitting ducks if their mission failed. Evn then it would be no guarantee any would escape.

So get known as a heavy defender with dips and maybe no one will mess with you.

quote: Originally posted by La Fayette on 01-09-2001 11:04 AM Dips cannot choose. Then, if you wish to destroy city walls, the worst that can happen to you is coming to the city with one dip per turn and getting three or four messages telling you that the unit under building has been destroyed. My advice would be: send one dip to have a look and tell how many improvements there are in the city (let us say n), then come back with at least n+1 dips to make sure that the walls go down.

2. Question 12.14 of
LINK: Info: Diplomats and Spies is relevant:
What is the probability that diplomat/spy+"use her judgement" will choose to sabotage a production?

quote: Originally posted by SlowThinker on 01-09-2001 05:42 PM I claimed at point 11.2 of LINK: Info: Diplomats and Spies that it is not cumulative It may be cumulative this way: Chance against one dip = 0.8 (80%) Chance against 2 dips = 0.8*0.8 (64%) Chance against 3 dips = 0.8^3 (^ means power) etc [This message has been edited by SlowThinker (edited January 10, 2001).]

Sorry I was not able to exhaust the archived info put forward on the subject so far, but ruoxiaohai asked and I looked for an answer in the manual rather than off the top of my head.

You say it is not cumulative, then you say it "MAY" be. Saying the chance against one dip is 80% is the same as the civ manual says 1 dip has 20% chance to thwart...6 of one/ half dozen of the other. After that it is only speculation as to exactly whats what

I know from experience it is, (to "some degree") the manual says it is.

Obviously it is not cumulative in the reasonable guess sense of:
1 dip = 20%, therefore 5 dips = 100% un stealable.
Since techs can still be stolen with even 6 dips inside this is not a correct conclusion.

But it is cumulative to some degree, and in a "practical sense" you can use this general knowledge to your advantage.

1)To simply know that the more dips you have in a city the better your chances of thwarting tech stealing

2)It is important simply to know that 5 dips or even one will not guarantee a theft will be thwarted.

3) It is simple to understand that someone wanting to steal will only go so far to do so. Well some folks anyway If you don't have some dips in vulnerable cities it will be very easy and surely worth while to those who steal techs.
If you have some dips in vulnerable cities, they may find it not worth while to steal and may actually research things for their own self

It is probably the reason we all keep playing ... the game always has a few surprises!

---------

1) Attack by 6 spies (non vet, use their judgment)
(since there are 5 improvements in the city, plus one under building)
Losses (after 25 attacks, which was judged to be enough, since the pattern was quite clear): 75 spies captured, 75 spies unharmed and promoted to veteran status.
This means exactly 50% losses.

Results (after 25 attacks):
Bank (ub) : 9, 5, 1, 2, 2, 6, =25
Barracks :12, 9, 4, 0, 0, 0, =25
Temple : 2,10, 9, 4, 0, 0, =25
Market Pl : 1, 0, 9,12, 3, 0, =25
Library : 0, 0, 0, 6,15, 4, =25
City Walls : 1, 1, 2, 1, 5,15, =25

(9 column one means that the bank under building was destroyed 9 times by spy #1)

The pattern is clear: almost a diagonal matrix, meaning that spies destroy almost according with the list of improvements, with a slight random factor (and a less clear pattern for the improvement under building).

2) Attack by 6 vet spies (use their judgmeent)

Losses (after 25 attacks): 43 vet spies captured, 107 unharmed.

Results:

Bank (ub) : 8, 4, 4, 2, 1, 6, =25
Barracks :12, 9, 4, 0, 0, 0, =25
Temple : 2,10, 9, 4, 0, 0, =25
Market P : 1, 0, 9,12, 3, 0, =25
Library : 0, 0, 0, 6,15, 4, =25
City Walls : 1, 1, 2, 1, 5,15, =25

(same pattern).
I intend to destroy some more improvements during the week-end. Results next week.

ST
Of course I put the main results on your thread when the fight is over .

1) Attack by 6 spies (non vet, use their judgment)
(since there are 5 improvements in the city, plus one under building)
Losses (after 25 attacks, which was judged to be enough, since the pattern was quite clear): 75 spies captured, 75 spies unharmed and promoted to veteran status.
This means exactly 50% losses.

Results (after 25 attacks):
Bank (ub) : 9, 5, 1, 2, 2, 6, =25
Barracks :12, 9, 4, 0, 0, 0, =25
Temple : 2,10, 9, 4, 0, 0, =25
Market Pl : 1, 0, 9,12, 3, 0, =25
Library : 0, 0, 0, 6,15, 4, =25
City Walls : 1, 1, 2, 1, 5,15, =25

(9 column one means that the bank under building was destroyed 9 times by spy #1)

The pattern is clear: almost a diagonal matrix, meaning that spies destroy almost according with the list of improvements, with a slight random factor (and a less clear pattern for the improvement under building).

2) Attack by 6 vet spies (use their judgmeent)

Losses (after 25 attacks): 43 vet spies captured, 107 unharmed.

Results:

Bank (ub) : 8, 4, 4, 2, 1, 6, =25
Barracks :12, 9, 4, 0, 0, 0, =25
Temple : 2,10, 9, 4, 0, 0, =25
Market P : 1, 0, 9,12, 3, 0, =25
Library : 0, 0, 0, 6,15, 4, =25
City Walls : 1, 1, 2, 1, 5,15, =25

(same pattern).
I intend to destroy some more improvements during the week-end. Results next week.

ST
Of course I put the main results on your thread when the fight is over .

Also looks as though the building/unit/wonder under construction doesn't get hit a second time once the production box is empty. (I have a feeling this has happened to me tho' - not when there is nothing left, or nothing but SDI, I mean. Can't place when tho'.)

There is a weighting towards less valuable improvements save that city walls have a generally lower probability but that lower probability can come in from hit one onwards.

All this accords with what unsystematised experience would suggest. Very nice to have it confirmed more authoritatively tho'.

Allez la France - keep up the good work.

quote: Originally posted by La Fayette on 01-12-2001 11:22 AM ST Of course I put the main results on your thread when the fight is over .

Good idea: I noticed this thread, but, in general, I may be engaded by other things, so it would be proper act to notice me about any new result.

Just got back from a fortnight in Murren - awesome despite poor snow.

Settlers (ub): 14, 4, 4, 3, 0, =25
Barracks_____: 10,14, 1, 0, 0, =25
Temple_______: 0, 6,15, 3, 1, =25
Market Place : 0, 1, 5,17, 2, =25
City Walls___: 1, 0, 1, 2,21, =25

(14 means that dip #1 destroys the settlers)

The pattern is the same as when using spies: almost a diagonal matrix, meaning that dips choose their target almost in accordance with the list (with a slight random factor).
The difference is the level of losses (all dips lost in the attack, instead of 50% of non vet spies and about 28% of vet spies).
I don't feel like testing vet dips now (I bet the pattern of results is the same and the level of losses somewhere between dips and non vet spies).

But I have tested an attack with spies choosing their primary target. Results hereunder.

1) 25 attacks by 6 non vet spies attempting to destroy city walls (I chose 6 because it was the number of spies used during the previous attack of Memphis,"use their judgment", see results above)
0 spy lost: 3 times
1 spy lost: 9 times
2 spies lost:6 times
3 spies lost:3 times
4 spies lost:1 time
5 spies lost:1 time
6 spies lost:2 times (which means that, unlike Jericho, the walls of Memphis did not come tumbling down).
Global losses are reduced, compared with the "use their judgment" attack: 51 spies lost instead of 75, but the attack fails twice out of 25 attempts.

2) 25 attacks by 6 vet spies attempting to destroy city walls:

0 spy lost : 5 times
1 spy lost : 16 times
2 spies lost: 3 times
3 spies lost: 1 time

Beloved vet spies! The walls tumble down and losses are quite light (25 spies lost in 25 attacks, which means exactly 1 loss/attack on the average).

I plan to be back with some results about poisoning and stealing techs within a few days (fed up with destroying improvements for the time being).

BTW there were neither dips nor spies inside Memphis and Nishapur.

Interesting. Very.

For non vets the trade off between letting the spy choose her target and specifying the walls seems to go something like

- non-selection guarantees some damage is done even if the walls never come down and the city is not taken; also calculating the number of spies needed to make the attack statistically close to a sure thing is easier.

- selecting the walls is a higher risk/higher reward approach; many spies may be lost for nothing at all; but the walls may come down at the first or second attempt with no or very few spies lost with some improvements retained in the city once it has been taken.

I, for one, have been getting this one wrong. My practice has been always to let the spy choose her target. I can now see that, particularly with vets, there are going to be tactical situations which favour specifying the walls. Attacking any city with a lot of improvements being an obvious one.

I have a feeling (empiric evidence only) that my attempts (outside communism) to make my spies into vets involve casualty rates at about 50%. So to get two vet spies I have had to build four. That still looks cheap compared to non vet results tho'.

Looking forward to results on poisoning etc. In case they throw up routes to vet status which are less costly.

Yes, Murren is in Switzerland. It is where recreational skiing started. It has enduring links with the UK but I also met quite a few Scandinavians and Dutch there. Not many French or German people.

If you like cutting yourself off from the world amongst a smallish group of other folk with whom you share an interest it is a really nice place.

Incredible views - I spent some minutes looking at the face of the Eiger mystified that folk climb it. Nowadays, apparently, free climbing - no ropes!

Like the sound of cheaper skiing in the Czech Republic. With tourism to central Europe picking up perhaps there is a cheap flight to be found. I might just look into it.

I did a quick test for sabotaging/use her judgement with
Barracks, Granary, Temple, MarketPlace, Bank, Cathedral, Recycl., SuperHighways, PoliceSt., with no recording. I felt Recycl., SuperH and Police were usually destroyed first, then choice skipped to the beginning of the list...

Description of tests:
50 attempts for each test:
Test 1: Vet spy - city walls, not the capital
Test 2: Vet spy - city walls, the capital
Test 3: Non-Vet spy - city walls, not the capital
Test 4: Vet spy - not city walls (ordinary improvements), not the capital
Test 5: Vet spy - not city walls (ordinary improvements), the capital
Test 6: Non-Vet spy - not city walls (ordinary improvements), not the capital
Test 7: Non-Vet spy - not city walls (ordinary improvements), the capital

I took notice of the survival after the attempt too: I imagined a spy attempt may be divided into two parts:
1. The enemy tries to capture a spy before completing her mission (the sabotage fails if he is succesful)
2. The enemy tries to capture a spy after completing her mission

I mark a succesful capture as 0, and an escape as 1: The result of a mission may be recorded as 0, 10 or 11:
0: The capture before the mission
10: Unsuccesfull capture before completing a mission (i.e. succesful sabotage) and succesfull capture after the mission
11: Unsuccesfull capture before completing a mission (and succesful sabotage) and an escape after the mission.

Results
Test 1: Vet spy - city walls, not the capital
0,0,11,10,11,11,11,11,0,0,10,0,11,0,11,10,0,11,0,11,11,0,0,11,11,0,0,10,0,11,10,0,0,0,10,10,0,11,10,0,10,10,11,0,0,10,0,11,10,0
22/50 (44%) captured before
16/28 (57%) escaped after

Test 2: Vet spy - city walls AND the capital
0,0,10,0,0,0,0,0,10,11,10,10,10,10,0,10,10,10,10,11,0,10,0,10,10,11,10,10,0,0,0,0,10,11,11,0,0,11,0,0,11,11,10,10,0,10,11,0,10,0
21/50 (42%) captured before
9/29 (31%) escaped after

Test 3: Non-Vet spy - city walls, not the capital
11,0,10,10,0,0,0,0,10,0,0,11,10,10,10,0,10,10,10,0,0,0,11,10,11,10,0,0,10,10,10,10,0,10,11,0,0,0,10,10,10,0,0,0,0,10,0,0,10,10
23/50 (46%) captured before
5/27 (18.5%) escaped after

Test 4: Vet spy - not city walls (ordinary improvements), not the capital
11,10,10,10,10,10,11,11,10,10,0,10,0,11,11,10,10,10,11,0,0,10,10,10,11,10,11,11,10,11,10,10,11,11,10,10,11,11,11,11,10,11,10,10,0,11,11,0,10,10
6/50 (12%) captured before
19/44 (43%) escaped after

Test 5: Vet spy - not city walls (ordinary improvements), the capital
10,10,0,0,11,11,0,10,10,10,10,11,0,11,11,0,10,0,11,11,11,11,0,10,11,11,0,0,11,11,0,0,0,0,11,11,11,0,11,11,0,10,10,10,0,0,11,11,11,11
17/50 (34%) captured before
22/33 (66%) escaped after

Test 6: Non-Vet spy - not city walls (ordinary improvements), not the capital
10,10,10,10,10,11,10,0,10,0,10,11,10,0,10,11,0,0,10,11,10,0,10,0,10,11,10,10,10,10,10,11,0,0,10,11,0,10,0,0,0,10,0,10,11,10,10,11,0,10,
15/50 (30%) captured before
9/35 (25.7%) escaped after

Test 7: Non-Vet spy - not city walls (ordinary improvements), the capital
0,10,0,10,0,10,10,0,10,10,10,0,10,10,0,10,10,0,11,0,0,0,0,0,0,10,10,0,0,10,10,0,0,11,10,11,0,0,0,0,0,0,10,0,0,0,11,11,0,0
28/50 (56%) captured before
5/22 (22.7%) escaped after

Summary:
Generally, I am confused. I am unable to find any simplifying rules.

Then, what is clear now from our tests?

1)"Use her judgment"

I think that the situation is quite clear when there is no specified target (which means attacking with dips or attacking with spies and choosing "use her judgment").
In that case, the improvements inside the city are destroyed almost in accordance with the list (my tests), with some sort of priority for some modern improvements (your tests).
City Walls are usually close to the bottom of the list.
Losses are 100% with dips, around 50% with non vet spies and around 29% with vet spies (almost certainly higher losses in a capital, but this remains to be tested).
In fact, it seems to me that the solution I gave before we started testing is still valid after test:

IF THERE ARE N IMPROVEMENTS IN THE CITY, ATTACK WITH N+1 DIPS OR SPIES ("using their judgment") and you are sure that the walls will tumble down.

2)"give primary target"
You are right, when 1 spy is lost she may be lost either before or after destroying the walls (O or 10, in your log).
I concentrated on "how many spies are captured during the attack", then the 2 situations "0,11" and "10" in your log both are one situation "1 spy lost" in my log.

I have converted your log into mine, in order to check whether your results are close to mine. Here it is (column 1=your test, column 2=my test):

Test 1: Vet spies; city walls; not the capital
O lost = 7,5
1 lost = 14,16
2 lost = 3,3
3 lost = 3,1
4 lost = 1,0
Total = 28,25

My conclusion: results quite in accordance (33 spies lost in 28 attempts in your test, 25 lost in 25 attempts in my test).

Test 3: Non vet spies; city walls; not the capital
0 lost = 3,3
1 lost = 15,9
2 lost = 4,6
3 lost = 3,3
4 lost = 1,1
5 lost = 2,1
6 lost = 0,2

Results also quite in accordance (46 spies lost in 25 attempts in your test, 51 lost in 25 attempts in my test).

3) What remains to be tested:
- vet dips (I don't wish to; I love vet spies, not vet dips)
- capital (I'll do some testing this week)
- improvements other than city walls (I'm satisfied with your test)

4) Am I confused?
Not at all. I think we are close to the end, since your tests provide results very close to mine.

(This is not the case when bribing cities without capital; I tell you about that later)