IntroductionStatistics is the study ofthe collection, organization,analysis, interpretation, andpresentation of data. Itdeals with all aspects ofthis, including the planningof data collection in terms ofthe design of surveys andexperiments.
History The use of statistical methods dates back at least to the 5th century BC. The earliest writing on statistics was found in a 9th century book entitled: "Manuscript on Deciphering Cryptographic Messages", written by Al-Kindi. In his book, he gave a detailed description of how to use statistics and frequency analysis to decipher encrypted messages, this was the birth of both statistics and cryptanalysis, according to the Saudi engineer Ibrahim Al-Kadi.
Collection Of Data 1. When information is collected by the investigator herself or himself with a definite objective in mind, is known as PRIMARY DATA. 2. The information was gathered from a source which already had the information stored, the data obtained in this way is known as the SECONDARY DATA.
Presentation of Data The Type Of Data we collected is known as raw data. We can present it in a number of ways like: 1. Frequency Table 2. Bar Graphs 3. Histogram 4. Frequency polygon 5. Line Graph. 6. Pie chart
A graph consisting ofrectangles whose areais proportional to thefrequency of a variableand whose width isequal to the classinterval. It was firstintroduced by KarlPearson.It is said to be derivedfrom the Greek histosanything set upright(as the masts of a ship)and gramma drawing,record, writing.
In a Frequency Polygon, aline graph is drawn byjoining all the midpoints ofthe top of the bars of ahistogram. A frequencypolygon gives the idea aboutthe shape of the datadistribution.The two endpoints of a frequencypolygon always lie on the x-axis.