Terms/Everything else Flashcards
Based of the correlation coefficient, how do we know if there is a strong or weak association?
The closer the correlation coefficient value is to +/- 1, the stronger the association
What is the range the correlation coefficient will always fall into?
The correlation coefficient will always fall between -1 and 1. If it doesn’t you did something wrong
What is the correlation coefficient used for?
The correlation coefficient is used to determine the strength of the association
How do we know what type of association we have based on the covariance?
If they covariance value is positive, we have a positive association. If it is negative, we have a negative association
What is the covariance used for?
The covariance is used to measure the linear association of data.
How do we know if data is skewed to the right or left?
Whatever direction has the tail with the least amount of the data is the direction of the skewness
What are the different types of skewness of a distribution?
No skewness (normal distribution), moderately skewed to the left/right, highly skewed to the left/right
How do we know if a z-score value is considered an outlier?
If the absolute value of a z-score is greater than 3, then we know if the value we are looking at is an outlier
What are z-score used for?
Z-scores are used to determine if a specific value is an outlier
What is a census?
A census is data collected on an entire population
What is Time-Series data?
Time-series data is data that is collected over several periods in time.
What is Cross-sectional data?
Cross-sectional data is data that is collect at roughly the same point in time
What is Quantitative data?
Qualitative data is numerical data (a.k.a quantitative variable)
What is Qualitative data?
Qualitative data is non-numerical data (a.k.a categorical variable)
What is ratio data?
Ratio data is numerical data that is used to compare elements
What is interval data?
Interval data is numerical data
What is ordinal data?
Ordinal data is the same as Nominal, however the order the data is in matters (Freshman, Sophomore, Junior, Senior, etc)
What is Nominal data?
Nominal data is data the involves non-numerical aspects like a label or name
How many observations are in a study?
n elements = ne observations (the number of observations equal the number of elements)
What is an observation?
An observation is measurements on a specific element (it consists of the entire row)
What is an element?
An element is what is being studied. A.K.A. the case
What is inferential statistics?
Inferential statistics is the process of using sampling data to infer an aspect of the population
What is descriptive statistics?
Descriptive statistics is the process of taking data and making it easily understandable (to the general public)
What is statistics?
The science of gathering, presenting, analyzing, and interpreting data
What is a frequency distribution?
A display of how frequent a certain result is acquired
What are the two types of dataset?
Grouped data and ungrouped (raw) data
What is a Cross Tabulation Table (Pivot Table)?
A Two-Way table
