Many classic children's board games, like Snakes and Ladder and Candyland, are essentially pure games of chance. Is it reasonable to regard Monopoly as a game of this type? How important is player skill (as opposed to luck) in Monopoly?
You didn't lay out criteria in your question so I'm going to assume that what you're asking is: Let's say Bob diligently acquires as much skill as possible in Monopoly and practices with 50 or more games. If Bob plays several beginners (10 or fewer games - little study of the game), and no players know other players' skill level - is Bob highly likely to win?
The answer is yes. Monopoly definitely involves skill, and therefore Bob is highly likely to win that first game.
The most sophisticated and difficult skill involves working favorable trades. Though trading occurs only a few times a game, it is the primary means by which skill can cause the odds of winning to shift dramatically.
To make favorable trades, you must:
There are also some simpler skills such as learning when it makes sense to buy a property and when to let it go up for auction, when it makes sense to start building houses (and how much money to keep in reserve), that the third house is the most valuable, etc.
Like Settlers of Catan, however, once it is clear who is the most skilled player, it is very easy for everyone to stop the most skilled player via trade embargos. I have had the experience several times of trouncing new opponents at Monopoly for a game or two and then losing more than average thereafter when my opponents refuse to trade with me. Actually - it's usually a little more gradual than that as first they just refuse to trade on my terms and start demanding more. And then they won't ever let me have a monopoly result from a trade. So then I resort to ever higher risk trades until I reach a point where nobody is willing to give me any trade I would want.
It is only when playing with fresh opponents that I have an opportunity to exert maximum skill, without fear that trading reputation will mean embargoes. That is why I carefully rephrased your question to assume lack of knowledge of the opponents. Because once it is clear who the most skilled player is in the game, it is very easy for opponents to gang up and actually cause the most skilled player to lose more often than average.
Side Note: several other answers imply that the luck of what you get has to be pretty good to even have a chance at making favorable trades. To that I say, you can make your own luck. For example, if you've studied Monopoly, you know that the two best monopolies to get in terms of risk/reward and Return on Investment are the oranges and light blues. So you may try trading for them earlier in the game. Many players are under the mistaken belief that Boardwalk is the best property. So if I obtain Boardwalk and I own one light blue, while the 2nd is owned by a different player and third by bank - I may offer Boardwalk for the light blue that is owned - and they think they are getting a steal. I now have two light blues and have created the possibility that I may get a monopoly if I get the third. So even though I had bad luck in not having 2 out of 3 of either light blue or orange, I have created a 2 out of 3 situation with one of the best two colors to increase my chances of getting lucky, or at least being able to trade for the 3rd.
In terms of skill versus luck level, I would put Monopoly on a similar plane to poker. That makes it more a matter of skill than the average dice game.
That is, between two comparably skilled players, luck will decide the winner.
It is possible for a skillful but unlucky player to beat a lucky, but unskillful player. But the skillful player would probably have to bluff a lot in order to win.
In my experience, Monopoly has more to do with luck than with skill. I define skill as the ability to make correct decisions. A decision is correct if it maximizes the odds of you winning.
It is possible to play Monopoly poorly (unlike, say, the card game War which is a game of pure luck and no decisions). For example, never buying anything and just collecting your $200 for each circuit will (against normal play) result in you eventually losing more money on each circuit than you earn. Therefore, some degree of skill is required by the game.
Usually you roll, you land somewhere, and you pay rent; no decision making. If the property is unowned, you have to decide if you want to buy it, but 99% of the time, buying it is the right thing to do. So there are two real sets of decisions; what trades do I make, and when and where do I buy houses.
Those few decisions have drastic impact on how the game unfolds, so sure, people who are more skilled at choosing wise trades and when to buy houses (for instance, is the extra $$ to be made from hotels more important the tying up the limited supply of houses?) will do better.
But those decisions are highly constrained by where the dice take them on all their previous turns. And like Joe said, that's a pretty bad ratio of useful decision-making to play time.
For sure, people who play with the house rule of putting money on Free Parking are skewing things away from skillful play even further.