Statistics Basics

Types of Statistics

• Descriptive Statistics: summarizes and describes the basic features of a dataset
• Inferential Statistics: uses sample data to make inferences about a larger population

Measures of Central Tendency

• Mean: average value of a dataset
• Median: middle value of a dataset when arranged in order
• Mode: most frequently occurring value in a dataset

Measures of Variability

• Range: difference between the largest and smallest values in a dataset
• Variance: average of the squared differences from the mean
• Standard Deviation: square root of the variance

Data Visualization

• Histograms: displays the distribution of a single variable
• Scatter Plots: displays the relationship between two variables
• Bar Charts: compares categorical data across different groups

Probability

• Experiment: an action or situation that can produce a set of outcomes
• Sample Space: set of all possible outcomes of an experiment
• Event: a set of one or more outcomes of an experiment
• Probability: a number between 0 and 1 that represents the likelihood of an event occurring

Hypothesis Testing

• Null Hypothesis: a statement of no effect or no difference
• Alternative Hypothesis: a statement of an effect or difference
• Test Statistic: a value used to determine the significance of the results
• P-Value: the probability of obtaining the observed results by chance

Correlation and Causation

• Correlation: a statistical relationship between two variables
• Causation: a cause-and-effect relationship between two variables
• Spurious Correlation: a correlation between two variables that is caused by a third variable

Types of Statistics

• Descriptive statistics summarizes and describes the basic features of a dataset
• Inferential statistics uses sample data to make inferences about a larger population

Measures of Central Tendency

• Mean is the average value of a dataset
• Median is the middle value of a dataset when arranged in order
• Mode is the most frequently occurring value in a dataset

Measures of Variability

• Range is the difference between the largest and smallest values in a dataset
• Variance is the average of the squared differences from the mean
• Standard Deviation is the square root of the variance

Data Visualization

• Histograms display the distribution of a single variable
• Scatter Plots display the relationship between two variables
• Bar Charts compare categorical data across different groups

Probability

• An experiment is an action or situation that can produce a set of outcomes
• Sample Space is the set of all possible outcomes of an experiment
• An event is a set of one or more outcomes of an experiment
• Probability is a number between 0 and 1 that represents the likelihood of an event occurring

Hypothesis Testing

• Null Hypothesis is a statement of no effect or no difference
• Alternative Hypothesis is a statement of an effect or difference
• Test Statistic is a value used to determine the significance of the results
• P-Value is the probability of obtaining the observed results by chance

Correlation and Causation

• Correlation is a statistical relationship between two variables
• Causation is a cause-and-effect relationship between two variables
• Spurious Correlation is a correlation between two variables that is caused by a third variable