Abstract: Aspects of the present disclosure are directed to a VC/XR connection system that can establish and administer an XR space for a video call. The VC/XR connection system allows users to easily transition from a typical video call experience to the XR space, simply by putting on her artificial reality device. The VC/XR connection system can identify calendared video call events, establish corresponding XR spaces, and create a link between the video call and the XR space. Invitees to the video call that don an artificial reality device can be automatically taken into the XR space. The XR space can A) connect to the video call as a call participant, allowing the video call participants to see into the XR space and B) show a feed of the video call in the XR space, allowing users in the XR space to see the video call participants.

Abstract: Aspects of the present disclosure are directed to a VC/XR connection system that can establish and administer an XR space for a video call. The VC/XR connection system allows users to easily transition from a typical video call experience to the XR space, simply by putting on her artificial reality device. The VC/XR connection system can identify calendared video call events, establish corresponding XR spaces, and create a link between the video call and the XR space. Invitees to the video call that don an artificial reality device can be automatically taken into the XR space. The XR space can A) connect to the video call as a call participant, allowing the video call participants to see into the XR space and B) show a feed of the video call in the XR space, allowing users in the XR space to see the video call participants.

Abstract: A social networking system determines whether targeting criteria for an advertisement includes one or more sensitive criteria. The advertisement's targeting criteria is compared to one or more keywords or parameters associated with sensitive topics, such as sexual orientation, religious affiliation, political affiliation, or health status. If the targeting criteria matches one or more keywords or parameters associated with a sensitive topic, the social networking system determines that the targeting criteria includes sensitive criteria and prevents recordation of information regarding a viewing user's exposure to the advertisement.

Abstract: An online system provides advertisers with opportunities to bid on presentation of advertisements to a user. Advertisers may bid in real-time on advertisement presentation if the online system determines the expected revenue to the online system from real-time bids is above a threshold value. The expected revenue may be determined based on a probability distribution bids previously placed by advertisers for presenting advertisements to the user or to users with similar characteristics as the user.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system modifies a bid amount associated with advertisements in an advertising campaign based on a target average price paid associated with the advertising campaign. A bid amount is determined from the target average price paid and associated with advertisements from the advertising campaigns in various advertisement selection processes. From advertisement selection processes in which an advertisement from the advertising campaign was selected, an average amount charged to the advertiser is determined. Based on the target average price paid and the average amount charged to the advertiser, the bid amount is modified. In subsequent advertisement selection processes, the modified bid amount is associated with advertisements from the advertising campaign.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: An online system provides advertisers with opportunities to bid on presentation of advertisements to a user. Advertisers may bid in real-time on advertisement presentation if the online system determines the expected revenue to the online system from real-time bids is above a threshold value. The expected revenue may be determined based on a probability distribution bids previously placed by advertisers for presenting advertisements to the user or to users with similar characteristics as the user.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: A social networking system provides suggestions of gifts to users for presentation to a target user for a life event of the target user. Merchants provide bids for their products. The social networking system selects products as gift suggestions based on the merchants' bids, recipient's interests, and the candidate user to whom the gift is suggested. The selected gift and any messages relating to the life event are held until a specified time and then delivered to the target user. At the time of delivery, the target user may be provided with alternative products that the target user can select instead of the gift. The social networking system can earn revenue based on promotion of products as gift suggestions, promotion of products as gift alternatives, and for any financial transaction related to the gift.

Abstract: An online system stores profiles describing characteristics of a plurality of users. An advertisement is presented to a first group of users. A subset of the first group, comprising a second group of users, provides explicit negative feedback for the advertisement. The negative feedback indicates the users' lack of interest in the advertisement. The online system identifies characteristics of the second group of users and determines a cluster of users other than the users in the first group. For each user in the cluster, the online system determines whether to provide the advertisement to the user based at least in part on the user's inclusion in the cluster.

Abstract: A social networking system stores a plurality of objects and displays advertisements related to the objects to users of the system. If a user dislikes an advertisement, the user may provide explicit negative feedback for the advertisement. When the social networking system receives the negative feedback, a list of reasons for the user's dislike is presented to the user, who may select one or more of the reasons. If the user selects a user-specific reason, the object represented by the advertisement is added to a negative interests list for the user. If the user selects an advertisement-specific reason, the negative feedback is used to determine a quality score for the advertisement.