## Revista Matemática Iberoamericana

### A geometry on the space of probabilities II. Projective spaces and exponential families

#### Abstract

In this note we continue a theme taken up in part I, see [Gzyl and Recht: The geometry on the class of probabilities I: The finite dimensional case. Rev. Mat. Iberoamericana 22 (2006), 545-558.], namely to provide a geometric interpretation of exponential families as end points of geodesics of a non-metric connection in a function space. For that we characterize the space of probability densities as a projective space in the class of strictly positive functions, and these will be regarded as a homogeneous reductive space in the class of all bounded complex valued functions. We shall develop everything in a generic $\mathcal{C}^*$-algebra setting, but shall have the function space model in mind.

#### Article information

Source
Rev. Mat. Iberoamericana, Volume 22, Number 3 (2006), 833-849.

Dates
First available in Project Euclid: 22 January 2007

https://projecteuclid.org/euclid.rmi/1169480032

Mathematical Reviews number (MathSciNet)
MR2320403

Zentralblatt MATH identifier
1122.46039

#### Citation

Gzyl, Henryk; Recht, Lázaro. A geometry on the space of probabilities II. Projective spaces and exponential families. Rev. Mat. Iberoamericana 22 (2006), no. 3, 833--849. https://projecteuclid.org/euclid.rmi/1169480032

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