Question

I need 3 to 6

Answer 1

1) Statistical Inference :
One of the main objectives of Statistics is to draw inferences about a population from the analysis of a sample drawn from the given population is known as Statistical Inference. In other words SI is a theory ,method and judgement to infer about the parameters of a population.

2) A sample may be drawn in number of ways. A random sample is a good representative of population as it ensures unbiasedness. and sample items are indiepentent to each other

3)Both mean and median have their own properties and are being used in appropriate ways.
for example if we are supposed to calculate average marks of a students in five subjects then we will use mean instead of mean and if we are supposed to calculate average income of a person living in a country we will compute median in place of mean.

4)Histogram is best in visualization of single distribution
For eg.If we have have a following data set, representing the number of students in different class intervals of marks of a particular subject.

Class interval	Frequency
10-30	10
30-60	20
60-80	25
80-100	10

in this case we will use histogram for data visualization,