Statistical Sampling and Market Returns Flashcards
2 broad meanings of stats?
Data
Method
What is the foundation for statistical inference?
Probability theory
Define:
Population
A population is defined as all members of a specified group.
Define:
Parameter
Any descriptive measure of a population characteristic
Define:
Sample
A subset of a population
Define:
Sample statistic
A descriptive measure of a sample characteristic
A sample statistic is a quantity computed from or used to describe a sample.
What are the four major measurement scales?
Nominal, ordinal, interval, or ratio.
We are examining cross-sectional data when…
We examine the characteristics of some units at a specific point in time.
Four types of ‘means’…
Arithmetic
Weighted
Geometric
Harmonic
Define:
Dispersion
Dispersion is the variability around the central tendency.
What are the 4 most common measures of absolute dispersion?
- Range
- Mean absolute deviation
- Variance
- Standard deviation
Define”
Absolute deviation
Amount of variability present without comparison to any reference point or benchmark.
How does one compute the mean absolute deviation?
- Sum the absolute difference between observations and the mean.
- Divide by n.
What is the main technical drawback of MAD?
It is difficult to manipulate mathematically compared with - variance…
What is the population variance?
Variance is defined as the arithmetic average of the squared deviations around the mean.
What is the population standard deviation?
Standard deviation is defined as the square root of the variance.