Abstract: Trust is calculated between persons for purposes of a business transaction. A measure of relative trust is determined for a target user with respect to a source user based on common entities that are related to both the users, for example, common relations, common background, or common preferences. A measure of absolute trust is determined for the target user using factors including financial information, work history, and so on. The absolute trust for the target user is improved using trusts of other users connected to the target user. The absolute trust and relative trusts are combined to obtain an overall measure of trust for the target user. The measure of trust for the user may be used for a business transaction, for example, lead generation, angel investment, equity crowd funding, and sharing of a product or service with another person.