Gender preference

Gender preference is a feature of a Sim's personality. It governs which gender a Sim, acting autonomously, may choose to interact romantically with.

Gender preference was introduced in The Sims 2 and carried forward into The Sims 3. In The Sims 2, it operates on a scale of -1000 to 1000, which SimPE represents as -10.0 to 10.0, rounded to the nearest tenth. In The Sims 3, it uses a signed, 32-bit integer.

Each Sim who is a teen or older has a set gender preference that is defined by the averaged total of all their romantic interactions with other Sims. For instance, if the majority of a Sim's romantic interactions have been with females, that Sim will have a preference for females, and vice versa, if the majority of the Sim's romantic interactions have been with males. Gender preference is fluid; a Sim's gender preference scores gradually change as they engage in romantic interactions with other Sims. Enough interactions can change a Sim's preference for a gender from negative to positive, or vice versa; e.g., a female Sim with a preference towards females who repeatedly has romantic interactions with male Sims may develop a preference for males. It is possible to influence the gender preference of townies and uncontrolled Sims by performing minor flirt interactions such as checking them out or whistling at them. Players with The Sims 2: University should note that autonomous flirting by an evil cow mascot will affect the gender preference of the Sim being flirted with.

In The Sims 2, the "Do You Like What You See?" interaction affects gender preference, even though it is an "Ask..." action and not a flirt interaction. However, the "Scope Room" self-interaction introduced in Nightlife does not affect Sims' gender preferences.

Newly created Sims, whether freshly out of CAS, or newly created townies, have a neutral gender preference, unless they are created as spouses. Most pre-made Sims have a neutral or nearly neutral gender preference; they either have no preference for either gender, or no preference for one and a slight preference for the other. In rare cases, a pre-made Sim may have a slight preference against one gender, but no preference toward the other. At least in The Sims 2, Sims who are born in-game or are adopted start their teen stage with a neutral gender preference.

Even though most townies and NPCs start with a neutral gender preference, they may still autonomously show attraction to Sims of the opposite gender, but the chances are lower than for Sims who have a preference for that gender.

In both The Sims 2 and The Sims 3, actions which change gender preference increase a Sim's preference for one gender by 2 and decrease that Sim's preference for the other by 1. This means that it is easier to move a negative preference toward zero than to move a positive one in that direction. So, a Sim can develop a positive preference for both genders, but this will not normally happen without deliberate, and probably repeated, action by the player. Also, a few pre-made Sims in The Sims 2 have pre-set positive preferences for both genders. It is not normally possible for a Sim to develop a negative preference for both genders, though it can happen with Sims who have a pre-set negative preference for one gender.

In general, the size of a Sim's preference for (or against) a gender affects how stable that preference is, rather than how strong it is. For example, a Sim with a -10/20 male/female preference isn't more attracted to females than one with a -1/2 preference. However, the first Sim's preferences will not be significantly affected if a male flirts with them once or twice, while the second Sim's will be.

Gender preference affects some gameplay mechanics. In Nightlife and later expansion and stuff packs for The Sims 2, Sims only show attraction and chemistry for Sims of their preferred gender, and only Sims of the preferred gender will be considered when a Sim uses the "Scope Room" self-interaction—though the gender preferences of the Sims being scoped will not be considered. This means that Sims with a neutral preference cannot use "Scope Room", but can be scoped. If a Sim has the same positive preference for both genders, the gender of the last Sim they interacted with romantically will be used. In The Sims 3: Generations, when a Sim throws a bachelor/bachelorette party, the gender of the entertainers will be based on the gender preference of the host.

A player-controlled Sim can be commanded to perform romantic interactions regardless of gender preference, though it appears to be more difficult for romantic interactions in The Sims 3 to succeed if the Sim being pursued has a gender preference not associated with the pursuing Sim.

Gender preference is a hidden aspect of Simology that can normally not be seen without the use of cheats, mods, or programs such as SimPE.
 * In The Sims 3, gender preference can be set with the use of mods such as NRAAS master controller.