Independent Events
What are Independent Events? In statistics and probability theory, independent events are two events wherein the occurrence of one event does not affect the occurrence of another event or events. The simplest example of such events is tossing two coins. The outcome of tossing the first coin cannot influence the outcome of tossing the second coin....
Mutually Exclusive Events
What are Mutually Exclusive Events? In statistics and probability theory, two events are mutually exclusive if they cannot occur at the same time. The simplest example of mutually exclusive events is a coin toss. A tossed coin outcome can be either head or tails, but both outcomes cannot occur simultaneously. Mutually exclusive events are commonly...
Frequency Polygon
What is a Frequency Polygon? A frequency polygon is a visual representation of a distribution. The visualization tool is used to understand the shape of a distribution. Essentially, the frequency polygon indicates the number of occurrences for each distinct class in the dataset. In addition, the graph may be used to show the cumulative frequency...
Cumulative Frequency Distribution
What is Cumulative Frequency Distribution? Cumulative frequency distribution is a form of frequency distribution that represents the sum of a class and all classes below it. Remember that frequency distribution is an overview of all distinct values (or classes of values) and their respective number of occurrences. The cumulative frequency distribution is extremely helpful when...
Bell Curve
What is a Bell Curve? A bell curve is the informal name of a graph that depicts a normal probability distribution. The term obtained its name due to the bell-shaped curve of the normal probability distribution graph. However, the term is not quite correct because the normal probability distribution is not the only probability distribution...
Positively Skewed Distribution
What is a Positively Skewed Distribution? In statistics, a positively skewed (or right-skewed) distribution is a type of distribution in which most values are clustered around the left tail of the distribution while the right tail of the distribution is longer. The positively skewed distribution is the direct opposite of the negatively skewed distribution. Central...
Negatively Skewed Distribution
What is a Negatively Skewed Distribution? In statistics, a negatively skewed (also known as left-skewed) distribution is a type of distribution in which more values are concentrated on the right side (tail) of the distribution graph while the left tail of the distribution graph is longer. While normal distribution is the most commonly encountered type...
Law of Large Numbers
What is the Law of Large Numbers? In statistics and probability theory, the law of large numbers is a theorem that describes the result of repeating the same experiment a large number of times. The large numbers theorem states that if the same experiment or study is repeated independently a large number of times, the...
Type I Error
What is a Type I Error? In statistical hypothesis testing, a Type I error is essentially the rejection of the true null hypothesis. The type I error is also known as the false positive error. In other words, it falsely infers the existence of a phenomenon that does not exist. Note that the type I...
Conditional Probability
What is Conditional Probability? Conditional probability is the probability of an event occurring given that another event has already occurred. The concept is one of the quintessential concepts in probability theory. Note that conditional probability does not state that there is always a causal relationship between the two events, as well as it does not...
