Research Methods 2 (Graphs/stats) Flashcards
Descriptive Statistics:
Overview of the data at a glance - ex. mean, median and mode
Histogram:
Type of graph used to report the # of times groups of values appear in a data set
Frequency Distribution
Type of graph illustrating the distribution of how frequently value appear in the data set
- the height is the frequency of the # in an underlying data set
Normal Distribution:
A distribution which a characteristic smooth, symmetrical, bell-shaped curve containing a single peak
Mean:
The average value of a data set
What are the Measures of Central Tendency and what do they tell us
Mean/ Median/Mode
- Tell us about the centre of typical value and not about the values around it
What can be influence by outliers
The Mean
What is an outlier?
extreme points, distant from others in a data set
How do you get the mean
adding all the #’s in the data set and and dividing by how many #’s in - the se
Mode:
he value that appears more frequently in the set of #’s
What can be used for non numerical sets
The Mode
Median
the centre value in a data set when the set is arranged numerically
- tells us where the middle of our data set is
Standard Deviation
average distance of each data point from the mean
Data sets with a larger deviation on a graph are…
more spread out
Data sets with a smaller deviation on a graph
less spread out
Inferential Statistics:
Statistics that allow us to use results from samples to make inferences about overall, underlying populations
what is a T-Test
A statistical test that considered each data point from both groups to calculate the probability that 2 samples were drawn from the same population
What is a P-Value
a value expressing the probability calculated by the T-Test
A T-test calculates
The P-Value e
What will the p-value be if it is statistically significant ?
the P-Value is less than 0.05
Statistical Significance
When the difference between 2 groups is due to some true difference between the properties of the 2 groups and not simply due to random variation
Correlation:
a measure of the strength of the relationship between 2 variables
What does +1 mean?
perfectly positively correlated; as one variable increases so does the other
What does -1 mean?
perfectly negatively correlated; one variable increases, the other decreases
What does it mean when the correlation coefficient approaches 0
the relationship between 2 variables, gets weaker,
- (no relationship between variables)
the closer the coefficient gets to -1 or +1
he stronger the relationship between the 2 variables
