Spring 2013
BA 275
Chapter 1: What is Statistics? (p. 2)
Types of Statistics
- Descriptive: methods of organizing, summarizing, and presenting data in an informative way
- Inferential: the methods used to estimate a property of a population on the basis
Week 7 - Notes
Chapter 9
Hypothesis Testing:
Can be used to determine whether a statement about the value of population
parameter should or should not be rejected.
The null hypothesis denoted by HO, is a tentative assumption about a
population parameter
Slides are online!
Email me if you need help: dechambe@onid.oregonstate.edu
Take Survey on Canvas and See assignment in Module 1 on Canvas
If you bought Cencage or book Sunday or money make sure you got the right one
people have been having a lot of probl
Week 5 Notes
Chapter 8
Interval Estimate of a Population Mean: if s is Unknown
X+/- ta/2 (s/ n )
Example:
Sample 16 efficiency apartments
Sample mean - $750 per month
Sample standard deviation - $55
Provide a 95% confidence interval estimate of the mean
Week 5
Biased: consistently over estimating or consistently under estimating
Unbiased sampling distribution = population mean
Variability:
Low variability tightly packed answers
High variability spread out answers
Margin of Error:
Point estimator cannot p
Week 2
PowerPoint is Online
Box Plot:
Graphical summary of data that is based on five-number summary: Low, Q1, Median,
Q3, High)
Easiest to identify outliers
Box is drawn with its ends at the first and third quartile and a vertical line is drawn
in the bo
Week 3
Distributions:
The higher the point the more distribution
Normal is symmetric or same on both sides and is defined by the mean
and standard deviation. The highest point on the normal curve is at the
mean, which is also the median and the mode.
Mean
Week 8 Notes
Chapter 9
Steps of Hypothesis Testing1. Develop the null and alternative hypotheses.
2. Specify the level of significance.
3. Collect the sample data and compute the test statistic.
p-value approach
4. Use the value of the test statistic to c
Appendix B: Tables
TABLE 1
CUMULATIVE PROBABILITIES FOR THE STANDARD NORMAL
DISTRIBUTION
Entries in the table
give the area under the
curve to the left of the
z value. For example, for
z = .85, the cumulative
probability is .1977.
Cumulative
probability
z
Chapter 8: Sampling Methods and the Central Limit Theorem (p. 224)
1. Sampling used to make inferences because of
1. Cost
2. Time
3. Limited value of additional information
4. Impossible to check entire population
5. Destructive nature of some tests
2. Ty
Chapter 3: Describing Data Numerical Measures (p. 30)
1. Measures Location v. Value
1. Location: pinpoint the center of a distribution of data
1. Average: measure of location that shows the central value of the data
2. Value
2. X vs. X
1. X is value of ea
Chapter 4: Displaying and Exploring Data (p. 98)
1. Location of a Percentile
1. Lp = (n + 1)* P/100
2. Measures of Position
1. Quartiles: divide a set of data into four equal parts, 3 Qs (Q1, Q2, and Q3)
2. Deciles: divide a set of data into ten equal par
Chapter 9: Estimation and Confidence Intervals (p. 257)
1. Point Estimate a value, computed from sample information, used to estimate
the population parameter
2. Confidence a range of values, constructed from sample data, that the population
parameter wil
Chapter 6: Discrete Probability Distributions (p. 166)
1. Probability Distributions a listing of all possible outcomes of an experiment and
the associated probability of each
1. Discrete: a number, specific outcome (not a range of values)
2. Continuous: o
Chapter 12:
1. F distribution
1. Tests whether two sample are from populations having equal variances
2. Compares several population means simultaneously analysis of variance (ANOVA)
3. Must follow a normal distribution and data must be at least interval-
BA 275 Exam Final Review
Chapter 12: Analysis of Variances (F)
Characteristics
- Family of distributions
- Continuous
- Cannot be negative
- Positively skewed
- Asymptotic
- Test statistic compares two sample variances
Hypotheses tests
- Comparing 2 pop
BA 275 Exam 2 Review
Chapter 8
Types of Samples (probability)
o Simple random: a sample selected so that each item/person in the population
has the same chance of being included
o Systematic random: a random starting point is selected between 1 and k, an
Chapter 10: One-Sample Tests of Hypothesis (p. 290)
1. Hypothesis a statement about a population parameter used for testing
2. Hypothesis testing procedure to determine if hypothesis is reasonable
3. 5 Step Procedure (6 steps)
1. State null and alternate
I.
II.
Review Econ 201
a. Specialization
i. Comparative advantage what if your specialty is obscure?
ii. Measuring the value of potential outputs to determine opportunity cost
iii. Use money to convert your effort into goods you didnt make
b. Motivation
i