Chapter 1-4 Flashcards
SAMPLING ERROR
The amount of error that exists between sample statistics and the population parameter
What is POPULATION
Is the entire set of the individual of interest for a particular research questions.
Statistics
Numerical value that describes a sample. A statistics is usually derived from measurement sin the population
1)Used to organize and summarize the information so that the researcher can see what happened in the study.
2)helped answer questions that initiated the research
Specific results obtained!
Parameter
Is a value usually a numerical value, describes a POPULATION measurements of the individual in a population
Correlational
Observe two different variable to see if they are related
Experimental
Manipulate one variable (independent)
While measuring the other variable (dependent).
CAUSE AND EFFECT
DESCRIPTIVE STATISTICS
Stats procedures used to summarize, organize and simplify data
Inferential statistics
Techniques to study SAMPLES and make generalization about the population.
Nominal
Set of categories with different names (college majors)
It represents who you are
Ordinal
Set of categories organized in order of magnitude or size
T shirts (S,M,L)
Interval
Equal distances between numbers arbitrary zero point. (0 degrees F)
Ratio
Interval scale with meaningful 0 point
Distance
Time
Real limits
Infinite possibilities in between
2 upper limit is 2.5 lower limit 1.5
How to make a frequency table?
Highest to lowest
—> frequency——> divide frequency with “N” to get proportion—-> multiply by 100
Frequency distribution
Organized tabulation of the numbers of observations located in each category on the scale of measurement
Set up a frequency table and calculate
Highest to lowest—>how frequent——>divide frequency with “N”—->proportion—>percentage
Calculate ΣX from frequency table
“X” multiply with “f” then add the sums together.
Calculate ΣX^2 from frequency table
Square the “X” ———>multiply by “f”——–>add everything together
How many rows would you need for a range X=41 X=96
Range calculate
Highest- lowest +1 = range
DIVIDE BY
INTERVAL WIDTH
Is the number of intervals
What graphs?
INTERVAL
Histogram and polygons
What graph?
RATIO
Histogram a and polygons
What graph?
NOMINAL
Bar graphs
What graph?
ORDINAL
Bargraph
What graph?
population
Smooth graph
How can you tell positive skew and negative
The thumb points in the direction.
Right hand positive
Left hand negative
Variability and how to measure
Tells us how much distance to expect from one score to another
Range/ standard deviation/ variance
How well represents in the entire distribution
Calculate Deviation
POPULATION
Deviation= X — mean
Tells us if the score is above or below the mean (— or +)
Square root SS over N
Calculate variance
POPULATION
Sum of squares
divide by
population(#)
Calculate Sum of Squares (SS)
POPULATION
1) Find deviation score (X-mean)
2) square each deviation
3) add all
Or
1) Square and Sum each score
2) find the sum —–>square it divide by “N”
3) subtract #2 from #1
Another name for squared deviation
Average squared deviation
Calculate standard deviation
POPULATION
Square root SS over N
POPULATION
Calculate variance then standard deviation
SAMPLE STATISTICS
SS over n-1
Adding a constant what will happen
Mean change
SD: not changed
Multiplying constant what will change
Mean change
SD change: multiply by constant
Measure Central tendency
Mean
Medium
Mode
More middle doesn’t tell you how spread out
Mean
Uses all scores
Center if gravity
Mew: population
Sample:M
Computational formula SS
1) Square each score and sum the squared scores
2) sum the normal scores, square it and divide it by “N”
3) subtract #2 from #1
Population standard deviation
Alternative description
Equation
Square root of the population variance
Square root SS/N
Population variance
Alternative description and equation
Mean squared deviation from the population mean
Sum of the mean subtracted by X and then squared over N
Sample standard deviation
Alternative description
Equation
A measure of the average distance from the sample means
Root of SS over n-1
Sample variance
Description
Equation
Mean squared deviation from the sample means
A squared
DISCRETE
Use what graph
Number of people
Solid whole numbers
Bar graph
Continuous
What graph
Time/height/weight
Real limits
(Upper real vs Lower real)
Histograms
What are the scales if measurements
Ratio
Nominal
Ordinal
interval
