Question

Give and example of a real life situation that includes: DATA STATISTIC PARAMETER How does the statistic and the parametere differ?

Answer 1

Example: A business man has factory for cakes. His machines are designed such that they make cakes having weight 5 kg. That means if you randomly take any cake from the shop, it should have weight equal to 5 kg.

Here the population is the cakes made by that factory. Our interest is in weight of cake.

In this case, population parameter or simply parameter is the quantity which describe population. Means mean weight of cake is 5 kg is the parameter.

After some years, owner wants to check the performance of machinery which makes the cake having weight 5 kg. For this, he take a sample of 100 cakes from the factory to check the performance. Here he has sample size of 100. Then he calculate the average weight for 100 cakes and test different hypothesis. The quantities which depends on sample known as statistics.

In this case, if he calculates average of 100 cakes and will get 90 kg. This value depends only on the sample, so it is a sample statistics or simply called as statistics.

Def:

A statistic is a characteristic of a small part of the population, i.e. sample. The parameter is a fixed measure which describes the target population. The statistic is a variable and known number which depend on the sample of the population while the parameter is a fixed and unknown numerical value.

Generally, if we have a large population size and want inference about it, we draw a sample and calculate statistics.