Supply and demand: Uber's surge pricing and economic models

Thanks to tutor2u for this comparison of 2 market approaches
http://www.tutor2u.net/economics/blog/ubers-surge-pricing-and-economic-models?utm_medium=email&utm_campaign=Economics%20daily%20digest%20Fri%2029th%20January%202016&utm_content=Economics%20daily%20digest%20Fri%2029th%20January%202016+CID_5deeb717a3b854cb2cbc275ebeb262c0&utm_source=CampMonitor&utm_term=Ubers%20surge%20pricing%20and%20economic%20models%20There%20have%20been%20a%20number%20of%20recent%20blog%20posts%20on%20the%20rise%20of%20Uber%20and%20whether%20its%20surge%20pricing%20benefits%20society%20There%20are%20arguments%20for%20and%20against%20but