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Probability and statistics

Statistical probability is a precise mathematical formula that aids us in comprehending and analysing our ignorance. It may not provide answers to queries about tomorrow's weather or the outcome of a future election, but it does present us with a framework that allows us to operate within the constraints of our limited knowledge and make rational decisions based on what we do not know.

Probability and statistics are the two most essential ideas in mathematics, and they are closely related. While Probability is concerned with chance, Statistics is concerned with how we handle distinct data sets with the use of a variety of statistical approaches. It contributes to the simplification of exceedingly sophisticated data in a very simple and understandable manner.

In situations where we are unsure about the result of an event, we speak of the probabilities of certain events occurring. Statistics is the study of events that are governed by chance and can be categorised into two categories.

As a result, if someone tells you that something has a high chance of happening, they are effectively telling you how likely it is that something will happen. When consumers buy lottery tickets, the likelihood of winning is usually given, and it is possible that the odds of winning are as low as 1/10,000,000. (or even worse). The likelihood of your winning is low, which indicates that you are unlikely to succeed.

Formula for Probability

The probability formula can tell us how many options we have out of a total number of possible combinations based on the number of choices we have. As a result, the following formula can be written:

In the field of statistics, methods for collecting, analysing, interpreting, and presenting empirical data are being researched and developed as part of an ongoing research and development effort.

What is the definition of statistics?

In the field of statistics, methods for collecting, analysing, interpreting, and presenting empirical data are being researched and developed as part of an ongoing research and development effort.

Uncertainty and variation are the two most fundamental concepts in the study of statistics, respectively.

Any measurement or data collection effort that is subjected to a variety of causes of variation and then repeated will most likely result in a different answer than the original one. Because of this, statisticians strive to first identify and then regulate the sources of variation in any given situation they encounter.

Probability Formula 

The formula for probability  tells us how many choices we have for the total number of possible combinations in the sample space. So, , the formula can be written as:

probability= possible choices/total number of choices

What is the definition of Statistical Inference?

Statistical inference is concerned with the process of making claims or conclusions about the properties of the genuine underlying probability measures that are being considered. These judgments must be founded on some kind of information, and it is evident that the statistical model is a component of that information. In addition to the observed outcome or reaction, which is referred to as the data, there is another vital piece of information.

Formula for Statistical Analysis

There are a few statistical formulas that can be used to aid in the solution of statistical problems. The formulas are listed in the following order:

Consider the item x to be the one that was provided, and the total number of objects to be n.

The mean is the sum of all the terms divided by the total number of terms.

  • Mean : sum of all the terms / total number of terms

  • Median: M = ((n+1)/2)th

      if n is odd.

M = [((n+1)/2)the term+(n/2+1)]th]/2

     if n is even.

  • Mode: Most frequently occurring value.

Probability and statistics terms are defined as follows

The following are some of the terminology that are commonly used in the concepts of probability and statistics:

  • Unpredictable Experiment: An experiment whose outcome we cannot predict until and unless it is observed is referred to as an unpredictable experiment. One of the most basic examples is tossing a pair of dice at random. We can be certain that the outcome will be unpredictable for us. The output can be any integer between 1 and 6 in the range of 1 to 6. As a result, this experiment is a completely random experiment.

  • A sample space is a collection of all of the possible outcomes or findings of a random experiment that can be considered. It is a collection of all of the conceivable outcomes that can occur when we throw a die at random.

  • Random Variables: These are the variables that represent the different outcomes that could occur in a randomly chosen experiment. Continuous Random Variables and Discrete Random Variables are two different forms of random variables. Discrete random variables can only have distinct values that are countable, and they cannot take any other values. Continuous random variables have an endless number of possible values since they are continuous.

  • Independent Event: When the likelihood of occurrence of one event has no effect on the probability of occurrence of another event, both events are referred to as independent events. In the case of a coin flip combined with a dice throw, the likelihood of receiving a “head” in the coin flip will be independent of the probability of getting a 6 in the dice throw.

  • The mean of a random variable is the average of the random values of the various outcomes of a random experiment; it is also known as the standard deviation.

  • The expected value of a random variable is defined as the mean of the random variable. In the case of a six-sided die, the expected value will be the average of all possible results, which is 3.5 in this case.

Conclusion

Statistical analysis is the study of data gathering and organisation. It consists the collection, analysis, interpretation, presentation, and organisation of data. It is a process of gathering and summarising information on a subject. This has a wide range of uses, ranging from tiny to large scale. Stats are used for all types of data analysis, whether it is the study of a country’s population or the research of the country’s economy.

Statistics has a wide range of applications in a variety of subjects, including sociology, psychology, geology, and weather forecasting, among others. Separate and continuous quantitative data are also distinguishable from one another. In contrast to discrete data, continuous data does not have a fixed value but rather has a range of values. There are numerous phrases and formulas that are used to describe this notion. 

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What is Discrete Random Variables ?

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