When a person unknowingly purchases travel insurance while having similar coverage under their household policy, this is an example of what?

The situation described involves a person acquiring travel insurance while already having similar coverage under their household policy. This scenario exemplifies dual insurance, which occurs when an individual is covered by two or more insurance policies for the same risk or set of circumstances.

In the case of dual insurance, while having overlapping coverage is not inherently problematic, it can lead to complications when a claim is made. The insured may find themselves in a position of having to navigate multiple policies to determine which insurer will be responsible for covering the loss. Insurers will often require that the insured informs them of any other policies in place that may cover the same risk to avoid disputes over which policy should respond to a claim.

The other concepts, such as coinsurance, reinsurance, and self-insurance, refer to different types of insurance arrangements. Coinsurance generally pertains to a provision where the insured shares in the costs of a loss, reinsurance is a practice involving an insurer buying insurance from another insurer to manage risk, and self-insurance involves an individual or entity setting aside funds to cover potential losses rather than purchasing an insurance policy. Thus, while relevant to insurance, these concepts do not apply to the situation presented.