introduction - econ.uiuc.edu · c. hurtado (uiuc - economics) spatial econometrics. on the agenda 1...

Introduction

Carlos Hurtado

Department of EconomicsUniversity of Illinois at Urbana-Champaign

[email protected]

Junel 20th, 2016

C. Hurtado (UIUC - Economics) Spatial Econometrics

On the Agenda

1 Introduction

2 Genesis

3 Environmental Systems Research Institute

4 QGIS

Introduction

On the Agenda

1 Introduction

2 Genesis

4 QGIS

Introduction

What do we do in Economic?

I What makes a theoretical model ”economics” is that the concepts we areanalyzing are taken from real life.

I Through the investigation of these concepts, we indeed try to understand realitybetter, and the models provide a language that enables us to think abouteconomic interactions in a systematic way.

I We do not view economic models as an attempt to describe exactly the world, orto provide tools for predicting the future.

I Although we will be studying formal concepts and models, they will always begiven an interpretation. An economic model differs substantially from a purelymathematical model in that it is a combination of a mathematical model and itsinterpretation.

I The word ”model” sounds more scientific than ”fable” or ”fairy tale”, but there isnot much difference between them. The author of a fable draws a parallel to asituation in real life and has some moral he wishes to impart to the reader.

C. Hurtado (UIUC - Economics) Spatial Econometrics 1 / 11

Introduction

What do we do in Economic?

I The fable is an imaginary situation that is somewhere between fantasy and reality.Any fable can be dismissed as being unrealistic or simplistic, but this is also thefable’s advantage.

I Being something between fantasy and reality, a fable is free of extraneous detailsand annoying diversions. In this unencumbered state, we can clearly discern whatcannot always be seen from the real world.

I On our return to reality, we are in possession of some sound advice or a relevantargument that can be used in the real world. We do exactly the same thing ineconomic theory.

I Thus, a good model in economic theory, like a good fable, identifies a number ofthemes and elucidates them. We perform thought exercises that are only looselyconnected to reality and have been stripped of most of their real-life characteristics.

I However, in a good model, as in a good fable, something significant remains.

Introduction

Choosing a Statistical Software

I There are many options to choose: R, Matlab, SAS, SPSS and Stata.

I Some of these programs are better adapt for a specific type ofanalysis.

I For example, Markov Chain Monte Carlo is doable in R, Matlab andSAS

I You can always write your oun script, but that may be uneficient.

I Learning how to program in any software will give you thefoundations to program in all languages

I For this computer lab we are going to use R and QGIS

Genesis

On the Agenda

1 Introduction

2 Genesis

4 QGIS

Genesis

At the beginning it was S

I Rick Becker and John Chambers created a language call S.

I It was not perfect, hence Robert Gentleman and John Chamberswanted to improve it.

I They both had an interest in statistical computing and saw acommon need for a better software environment to run in theirMacintosh teaching laboratory at University of Auckland.

I They decided to write their own interpreter of S, rather than adoptone the many free S interpreters available at the time.

I The initial interpreter consisted of about 1000 lines of C code andprovided a good deal of the language functionality found in thepresent version of R.

I Later they improve upon S and consolidated their program R.

Genesis

R is a Free Software

I The authors produced what looked like a potentially useful piece ofsoftware and we began preparing it for use in our teaching laboratory.

I The placed the first binary copies or R at Statlib and started amailing list in August 1993.

I A number of people picked up the binaries and offered feedback.

I The most persistent of these was Martin Machler of ETH Zurich, whoencouraged the authors to release the R source code as ”freesoftware”

I Given that R is free interest in R grew. As R developed and peoplebegan porting applications to it.

Genesis

I People outside the free software movement frequently ask about thepractical advantages of free software.

I Nonfree software is bad because it denies your freedom. Thus, askingabout the practical advantages of free software is like asking aboutthe practical advantages of not being handcuffed.

1 The freedom to run the program as you wish, for whatever purpose.2 The freedom to study the program’s ”source code”, and change it, so

the program does your computing as you wish.3 The freedom to make and distribute exact copies when you wish.4 The freedom to make and distribute copies of your modified versions,

when you wish.I With proprietary software, there is always some entity, the ”owner” of

the program, that controls the program and through it, exercisespower over its users.

Genesis

Environmental Systems Research Institute

On the Agenda

1 Introduction

2 Genesis

4 QGIS

I Esri, Environmental Systems Research Institute, is an internationalsupplier of Geographic Information System (GIS) software.

I The company was founded as Environmental Systems ResearchInstitute in 1969 as a land-use consulting firm.

I Esri products (particularly ArcGIS Desktop) have 40.7% of the globalmarket share.

I What is ArcGIS?- Aeronautical Reconnaissance Coverage Geographic Information System

I Esri, Environmental Systems Research Institute, is an internationalsupplier of Geographic Information System (GIS) software.

I The company was founded as Environmental Systems ResearchInstitute in 1969 as a land-use consulting firm.

I Esri products (particularly ArcGIS Desktop) have 40.7% of the globalmarket share.

I What is ArcGIS?- Aeronautical Reconnaissance Coverage Geographic Information System

I ArcGIS is a geographic information system (GIS) for working withmaps and geographic information.

I It is used for:- creating and using maps- compiling geographic data- analyzing mapped information- sharing and discovering geographic information- using maps and geographic information in a range of applications- managing geographic information in a database

I ArcGIS is a geographic information system (GIS) for working withmaps and geographic information.

I It is used for:- creating and using maps- compiling geographic data- analyzing mapped information- sharing and discovering geographic information- using maps and geographic information in a range of applications- managing geographic information in a database

I The shapefile format is a popular geospatial vector data format forgeographic information system (GIS) software.

I It is developed and regulated by Esri as a (mostly) open specificationfor data interoperability among Esri and other GIS software products.

I The shapefile format can spatially describe vector features:- points (water wells)- lines (rivers)- polygons (lakes)

I Each item usually has attributes that describe it, for example, name,population, etc.

I The term ”shapefile” is quite common, but is misleading since theformat consists of a collection of files with a common filename prefix,stored in the same directory.

I The three mandatory files have filename extensions .shp, .shx, and.dbf

I The actual shapefile relates specifically to the .shp file, but alone isincomplete for distribution as the other supporting files are required.

- .shp - shape format; the feature geometry itself- .shx - shape index format; a positional index of the feature geometry to

allow seeking forwards and backwards quickly- .dbf - attribute format; columnar attributes for each shape, in dBase IV

format

On the Agenda

1 Introduction

2 Genesis

4 QGIS

I QGIS (previously known as Quantum GIS) is a cross-platform free andopen-source desktop Geographic Information System (GIS)application that provides data viewing, editing, and analysis.

I QGIS allows users to create maps with many layers using differentmap projections. Maps can be assembled in different formats and fordifferent uses.

I QGIS integrates with other open-source GIS packages, includingPostGIS, GRASS, and MapServer to give users extensive functionality.

I Plugins written in Python or C++ extend QGIS’s capabilities.

introduction - econ.uiuc.edu · c. hurtado (uiuc - economics) spatial econometrics. on the agenda 1...

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