Feb. 11th 2016Key Box: ***: Know for test
EXAM 2 (NOT OPEN BOOK) will consist of:
∙ 9 Multiple Choice
∙ 3 Fill-in-the-blank
∙ 1 True/ False
∙ 3 problems to work
The entire objective part on the exam consist of these notes!
On exam, know: names, ranks, definitions, and examples!
***: Definition ***: Titles
ALL DEFINITIONS IN THESE NOTES WILL BE ON THE NEXT EXAM!
❖ 4 Types of Data
o Types of measurement scales= Data (same thing)
o Ranked from weakest to strongest
▪ Below is the correct order!
1. Nominal (weakest): Numbers are used to represent names (names/classification, etc.) a. Ex: Social Security (most used version of this type of data) Don't forget about the age old question of What are the six economic indicators?
b. Weak ???? Calculate mean- doesn’t really tell you anything
2. Original: Data which has been ranked OR put into order If you want to learn more check out What is the study of human movements by identifying the anatomical elements?
If you want to learn more check out If 200.0 g of zinc sulfide contains 134.2 g of zinc, how many grams of sulfur can be obtained from 1.18 kg of zinc sulfide?
Don't forget about the age old question of What group does benzopyrene belong to?
a. Can’t do much with it, but you do use it to put things in rank
b. Ex: Sport rankings, movie rankings, etc.
3. Interval: Data where the numbers mean something, but there is NO ONE TRUE ZERO POINT
a. You can find the mean, but no true zero point
b. Ex: Temperature ???? each version (Fahrenheit or Celsius) has their own different zero point
4. Ratio (strongest): Data where the numbers mean something and there is a true zero a. Ex: GPA—The numbers tell you something
b. MOST OF WHAT WE DO IS RATIO DATA!
❖ Time Series
∙ A set of values/data measured at successive points in time over a given time period ∙ Reference example problems given in class
o 1st column= Time
o 2nd column= Data We also discuss several other topics like What is the purpose of capitalism?
∙ We will use it to measure future data
o What we will be doing: Taking what is given and forecasting future data A. Components of a time series:
1. Trend – the gradual shifting of the time series value usually because of long term factors.
a. Long-term = more than a year
b. Long- term factors that affect trends include:
i. Changes in the population ???? change in size If you want to learn more check out What is a valence electron?
ii. Changes in the demographic characteristics of population
iii. Changes in technology
iv. Changes in consumer preferences
v. Economic changes???? mainly inflation
2. Cyclical – an up and down movement over a long time period ???? usually last MORE
THAN a year
a. Like a legit cycle of events:
3. Seasonal – shows changes in the historical data within ONE YEAR usually because of seasonal influences
a. Seasonal change ???? weather
4. Irregular – explains changes in actual time series values which cannot be explained by any other components.
a. Irregular components CANNOT be predicted using historical data. Usually due to acts of God: unanticipated, nonrecurring factors.
i. Ex: tornado, hurricane, flood, etc.
1. One can see it coming, cannot predict what it will do or when
another will come
B. Time Series Forecasting using SMOOTHING method:
a. Smoothing – smoothing out irregular factors because smoothed values have less variation than the raw data
b. Smoothing techniques:
i. Simple moving average (simplest)
ii. Weighted moving average
1. Problem will give “weight” ???? check problem #2 for example
iii. Exponential smoothing (hardest to grasp)
∙ If the problem sates just “moving average”, go with the simple moving method ???? check prob. #1 for example
∙ After working all, we can determine which way to work it is best
NOTE FROM DR.TANNER:
PLEASE ONLY USE THESE NOTES AS A REFERENCE. DO NOT MISS CLASS JUST BECAUSE YOU CAN BUY THE NOTES.