Statistics Flashcards
Inferential Statistics
Using sampled data to draw conclusions or make predictions about a larger sample, data sample, or population
Descriptive Statistics
Analyze data to help describe, show, or summarize it in a meaningful way
Statistical Significance
Helps indicate whether or not the result is likely due to chance or to some factor or interest
- if p (probability) is less than 0.05, there is a 95% chance that the study’s results are not due to randomness, bias, or confounding variable
- smaller the p-value, the more significant the results
Goal: disprove the null hypothesis, which predicts the results cannot be applied to a larger population
Null Hypothesis
Predicts there will not be a significant relationship
- if the results are significant: reject nh :)
If the results are not significant: accept nh :(
Mean
Data’s average score of the sample
Median
middle score after the scores had been arranged in numerical order
Mode
The most frequent value occurring
Skewed Data
When frequency data is not spread evenly (ie: normally distributed); the data is clustered to one end
Positively Skewed
Elongated tail at the right
Negatively Skewed
Elongated tail at the left
Bar Graph
A graph in which bars of varying height with spaces between them are used to display data for variables defined by qualities of categories
Histogram
Used to portray the grouped frequency distribution of a variable at the interval or ratio level of measurement
Bar graph vs Histogram: space
Bell Curve
Bell-shaped, symmetrical graphical illustrations when values such as mean, median, mode sit at the center of the bell
Z-score
Measures exactly how many standard deviations above or below the mean a data point is
Standard Deviation
A measure of scatter in a data set relative to the data’s central mean value
Ex: if the IQ of some group has a standard deviation of 10, most of the group will have an IQ within approx 10 points of the mean
- 15 above and below the standard deviation is the
