Statistical Aid
859 FOLLOWERS
Statistical aid is a site which provides statistical content, data analysis content and also discuss the various fields of statistics.
Statistical Aid
4y ago
Definition
In statistics, the statistical data whether qualitative or quantitative, are generated or obtain through some measurement or some observational process. Measurement is essentially the task of assigning numbers to observations according to certain rules. The way in which the numbers are assigned to observations determines the scale of measurement being used. There are four level of measurements in statistics. They are-
Nominal Level
Ordinal Level
Interval Level
Ratio Level
Nominal Level of Measurement
All qualitative measurements are nominal, regardless of whether the cate ..read more
Statistical Aid
4y ago
Definition
Forecasting is the process of making prediction of the future based on past and present data.
In many cases a reliable forecast can be worth a lot of money, such as consistently and correctly guessing the behavior of the stock market for enough in advance to act upon such a guess.
Objectives of forecasting
In narrow sense, the objectives of forecasting is to produce better forecast. But in the broader sense, the objective is to improve organizational performance, more revenue, more profit, increased customer satisfaction etc. Better forecast by themselves are no inherent val ..read more
Statistical Aid
4y ago
Definition
Inference comes from a word ‘infer’ which means that to draw a conclusion about a phenomenon on the basis of some information at hand. To make inference about a phenomenon through some statistical procedure is called statistical inference. Inference may be divided into two categories. They are-
Inductive Inference
Deductive Inference
Inductive Inference
By inductive inference we mean to draw a conclusion about a small part of the phenomenon and generalized it for the whole phenomenon. The research worker performs an experiment and obtain some data on the basis of the data ..read more
Statistical Aid
4y ago
Time series data
A time series data is a set of observation on the value that a variable takes of different time, such data may be collected at regular time intervals such as daily stock price, monthly money supply figures, annual GDP etc. Time series data have a natural temporal ordering. This makes time series analysis distinct from other common data analysis problems in which there is no natural order of the observation. In simple word we can say, the data which are collected in according to time is called time series data.
On the other hand, the data which are collected by observing many ..read more
Statistical Aid
4y ago
Definition
An experiment is a well defined act or an investigation conducted to discover the underlying facts about a phenomenon, which are utilized to test some hypotheses of interest to verify the results of previous investigations. More precisely, an experiment is the process of data collection from a non-existent population to get answer to the certain problems under investigation. There are two types of experiment. They are-
Absolute experiment: An absolute experiment is one in which the absolute value of some characteristic is determined. Sample survey belongs to absolute experiment ..read more
Statistical Aid
4y ago
Definition
The relationship between two or more random variables are generally defined as the correlation. It is the major part of bivariate analysis. When variables are found to be related, we often want to know how close the relationship is. The study of the relationship is known as correlation analysis. The primary objective of correlation is to measure the strength or degree of linear association between two or more variables. For example, we may be interested in measuring the relationship between the-
Height and weight of the people of certain area.
Ages of husband and their wives.
A ..read more
Statistical Aid
4y ago
Skewness
Literally, skewness means the 'lack of symmetry'. We study skewness to have an idea about the shape of the curve which we can draw with the help of the given data. A distribution is said to be skewed if-
Mean, median, mode fall at different points, i.e, Mean ≠ Median ≠ Mode.
Quartiles are not equidistant from median.
The curve drawn with the help of the given data is not symmetrical but stretched more to one side than the other.
The lack of symmetry in a distribution is always determined with reference to a normal distribution, which is always symmetrical. Any departure ..read more
Statistical Aid
4y ago
Discrete Probability Distributions
There are some discrete probability distributions which are very important part of statistics are following-
Bernoulli Distribution
Binomial Distribution
Poisson Distribution
Negative Binomial Distribution
Geometric Distribution
Hypergeometric Distribution
Multinomial Distribution
Power Series Distribution
Discrete Uniform Distribution
Logarithmic Series Distribution
Continuous Probability Distributions
Some impotant continuous probability distributions are following-
Uniform Distribution
Normal Distribution
Gamma Distribution
Triangular Dist ..read more
Statistical Aid
4y ago
Population variance and standard deviation
The average of the square of the deviations taken from mean is called variance. The population variance is generally denoted by σ2and its estimate (sample variance) by s2. For N population values X1,X2,...,XN having the population mean μ, the population variance is defined as,
Where, μ is the mean of all the observations in the population and N is the total number of observations in the population. Because the operation of squaring, the variance is expressed in square units and not of the original units.
So, we can define ..read more
Statistical Aid
4y ago
Gamma Distribution
A continuous random variable X is said to have a generalised gamma distribution with parameter α and β if its probability density fumction is defined as,
Where α and β are two parameter and α,β>0 ..read more