321_F11_slides2

321_F11_slides2 - Review of Econ 221 Part I Econ 321 Click...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style Econ 321-Stéphanie Review of Econ 221 Part I Econ 321 Introduction to Econometrics Wooldridge: appendices A & B & C 11
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Econ 321-Stéphanie Main Steps in Statistical Analysis Population and Samples Population and Sample Distribution Estimation Central Limit Theorem 22
Background image of page 2
Econ 321-Stéphanie Populations and Samples What is a population? The group or collection of all possible entities of interest (populations are infinitely large) What type of population would you be concerned with in your life? Population parameter What is a sample? Why use a sample rather than populations? 33
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Econ 321-Stéphanie Example for the use of Samples We are interested in a training program which is supposed to improve productivity. It would be very expensive to implement throughout a firm, particularly if it doesn’t work. Instead, we set up an experiment in which we try the program on a sample of employees at a single location (a pilot 44
Background image of page 4
Econ 321-Stéphanie Example for the use of Samples We experiment with a pilot program and find that productivity rose by 2% Our problem in using the pilot (sample): if we replicate the pilot throughout the firm is it reasonable to believe that we will get a 2% boost in productivity? could this just be the result of getting a “good” sample (those who happened to respond favorably to the program)? Our core problem in using samples is distinguishing between systematic effects of programs and chance outcomes 55
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Econ 321-Stéphanie Sampling Variability Samples are affected by randomness Samples are not an exact reproduction of the population 2 samples drawn from a population are unlikely to be identical The sample mean is likely to be different from (but close to) the population mean 66
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/29/2011 for the course ECON 321 taught by Professor Louis during the Fall '09 term at Waterloo.

Page1 / 28

321_F11_slides2 - Review of Econ 221 Part I Econ 321 Click...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online