Chapter 4 (even more)
In general, the standard deviation (SD) does not change if each number in the list is increased by
the same amount.
The same is true if each number is decreased by the same amount
o Suppose each number in the list 1,5,5,7,7,
The median also follows rule similar to average.
o If you add the same value to all numbers in a list, the median of the list is increased by
the same value
o If you multiply all numbers in a list by the same value, the new median is just the old
Chapter 10: Regression
The regression method describes how one variable depends on another
o To get started, look at the scatter diagram
Measure Errors: Chapter 6
o 103= kilo
o 106= mega
o 109= giga
o A million seconds is about 12 days
o A billion seconds is about 31 years
o A trillion seconds is about 31,688 years
U.S. National debt is about 19 trillion dollars. T
Chapter 5: Normal Approximation for Data
o Given a list of numbers, the percentile corresponding to a given value x can be computed
Percentile= (number of values below x +0.5/total number of values)100
Ex. A teach give a 20- pint
Chapter 3 (continued)
A variable is a characteristic which changes from person to person in a statistical study
o Here are some examples:
The income of a household
The marital status of a person
The makes of cars own by people
The family size in a cou
What is Statistics?
Data collection: is collected by performing statistical experiment
o 2 designs
Ex. A new drug is discovered. How should an experiment be designed to test its effectiveness?
o We divide the
Controlled experiment as well as observational studies are good methods for collecting data.
However, observational studies are not as successful as controlled experiment.
In a controlled experiment, the investigator decides who will be in the cont
Chapter 8: Correlation
The knowledge of the relationship b/t two variables will help us to answer questions like
o Does blood pressure level predict life expectancy?
o Do SAT scores predict college performance?
o Do taller women marry taller men?