All of the above.  I paste below a section excerpted from a recent chapter I have written.

The emergence and adoption of autonomous vehicles is expected to accelerate certain trends already underway in terms of shared urban mobility, and to enable new mobility service models that bridge traditional transit service and personal mobility, resulting in new hybrid forms....These potential changes in the supply of transportation and mobility at the urban scale are difficult to predict and characterize for the purpose of developing specific planning tools, and forecasting the demand for these services over time.  

While it may be difficult to predict exactly which services may emerge in a certain locale, and the extent and type of demand these might serve, the following aspects can be noted based on current understanding of travel behavior and the expected features of autonomous vehicles.

a.    It is a given that driverless vehicles will enable new forms of mobility supply.  By eliminating the cost and performance limitations of human drivers, and increasing the ease of communicating instructions to both vehicles and travelers, autonomous vehicle fleets can be operated efficiently to deliver dynamically scheduled services to individuals riding privately or in shared vehicles.

b.    New forms of car sharing with greater convenience may reduce the motivation for individual ownership.  With driverless cars, availability of a vehicle in sharing services such as Zipcar and Enterprise car share (formerly Igo) is not limited to the nearest lot. Vehicles can be repositioned dynamically to the user’s location from anywhere in the city.

c.     Ride and car sharing marketplaces will likely expand with driverless vehicles, following, for example, platforms developed by ride-hailing app companies like Uber and Lyft.  This would contribute to reducing the cost and uncertainty of the sharing model by increasing the supply pool and enabling rapid dispatch of driverless vehicles.

d.    The realm between personal transportation and public mobility can widen considerably to include various hybrid forms.  Many agencies have already embraced a spectrum or suite of services in order to reduce operating costs in lower-density metropolitan areas. Experimenting with a fleet of smaller vehicles, casual sharing, and more traditional vanpools and guaranteed ride home programs, agencies have explored many options to move people over low-density areas or at odd times of day. Services in this spectrum, which fall between purely fixed-route and purely demand-responsive and can be described as “semi-flexible”. These services typically include a set of stops with a predetermined schedule along with sections of a service area where service is flexible (e.g. route deviation), possibly with door-to-door service. The premise of these services is that in low-density areas, certain points will have higher demand at different times of day (e.g. hospitals, dedicated guideway transit, major employment/retail centers). Imposing some structure, but still allowing flexibility, can create more efficient tours while remaining intuitive and user-friendly.  With autonomous vehicles, greater dispatching flexibility is possible, enabling the equivalent of personalized service at times, and shared rides at others, depending on the specific demands prevailing at a certain time.

e.    What will become of public transit as we know it?   With transit companies adopting a broader portfolio of services, possibly in conjunction with third parties, one could envision disappearance of conventional fixed-route, fixed-schedule bus service in most lower-density communities, supplanted by driverless, personalized service at low density and shared hybrid forms at medium densities; and greater focus on frequent rapid service along dedicated right of way (rail and/or BRT) in higher-density travel corridors, made more efficient and accessible via driverless hybrid options.

Some of these trends are beginning to emerge today.  Several communities are experimenting with hybrid forms of public transit. Car sharing programs are thriving in many cities.  Ride-hailing app companies (Uber, Lyft) that dramatically increase the pool of available vehicles to serve customer requests (albeit on still controversial regulatory grounds) have become household names in many cities around the world.  Some of these same companies, especially Lyft, are making a concerted effort to tailor services to better complement existing transit services by, for example, providing access to rail transit stations (e.g. http://take.lyft.com/friendswithtransit/, accessed December 21, 2015).  In Finland, the city of Helsinki received a lot of attention in transportation planning circles when it announced its goal of no more private car ownership in the city, all the while while offering individual and shared public personal urban mobility through a city-managed virtual platform.  

Thanks Hani, that is a global view of the future models of operation with self-driving cars.

In this exercise it is difficult to know what will be the prevalence of each model and the timing for such models to take place in the market. 

It is also to noticeable some factors that will led to car share or car rent:

- The fact that the driver is not in power of the driving act will represent a detachment as many feel the car as an extension of themselves.

- The self-drivers we know are not fancy, they are more likely to be known as transportation than cars.

- The practical aspects, as one will not need to park, to repair or to pay for maintenance.

- The cost tend to be lower as it represents like a pay per use and not the initial investment and the a permanent cost in insurance.

The most interesting to notice are the business models that will appear and those to be extinct as for instance cabs or taxis will lose market for sure and new companies will emerge to provide such services.

One of the major factors for wanting to own a vehicle is the "mobile storage" aspect, and privacy.  People with kids keep all sorts of practical things in their cars; sports enthusiasts keep gym clothes, tennis racket; hobbyists have tools,  etc..   Then there is the touch and smell factor-- people pay high premiums for luxury cars.   Also, cars will become moving computers-- same way you keep your own laptop with your stuff on it you may want to keep your own apps, music, etc.. (though cloud-based systems could take care of that).

Yes Hani, in fact cars are storage places and it gives a personal touch that we like. The computational side is easily addressed, each of us can have a session that will access to all services remotely in the cloud or something else that will appear next. 

I also think that some will have concerts of higiene! sometimes people have such concerns with bacteria, dirt and smells. That will be a challenge for the companies as if the car is circulating all day picking and leaving people it is not likely that will be clean. We may jus wonder what people will do inside a car that is not theirs and nobody is watching !! unless they will put cameras and detectors in such cars.

Hi Fernando, interesting question that you brought up! Maybe a paper that I (together with my co-authors, Sven Beiker and Barbara Lenz) published only recently could be of interest to you in this regard:

Article Transition pathways to fully automated driving and its impli...

Interesting your comments John Vaala Miller . In fact in this question I only mentioned the public/private aspect while there is a wide range of aspects to be concerned. Just to mention, the ethical decisions are probably the most critical and most defying regarding the widespread circulation of self-driving cars in our roads, as it is expected to come from the MIT moral machine (moralmachine.mit.edu). One of the most concerning aspects is the coexistence of traditional cars and self-driving, one of the issues debated in an article I published at the ASME/IMECE conference in 2016 (https://asmedigitalcollection.asme.org/IMECE/proceedings-abstract/IMECE2016/50527/V002T02A038/265235) It also covers some other aspects related to self-driving cars. As you well notice, COVID-19 (and the possibility of other pandemics) is a game changer since a high concern about who previously used a shared car and the risk of contamination. In fact this implies more gear to be added to self-driving cars for public/shared usage since it is necessary to ensure disinfection and proper sanitary conditions for new clients.

Testing is in fact a need for ensuring safety as well noticed by Kasyap Suresh

I am interested in the cooperation.

Is there a possibility of doing the research here in Tunisia?