การวิเคราะห์ผลการออกเลขท้าย 3 ตัวและเลขท้าย 2 ตัวรางวัลที่หนึ่งของล๊อตเตอรี่

Abstract

The objective of this research is 1) to study the frequency of number occurrence in the last 3 and 2 digits of the first prize 2) to study the relationship between the last 3 digits and the last 2 digits of the first prize 3) to compare the proportion of the winning number with the classical probability of that number, and 4) to find the expected return on the investment of 1 lottery ticket. The data of Thailand lottery is collected from the past 30 years until now, 750 times. The statistics that were used were: frequency classification, percentage, mean, standard deviation, t-test, chi-square, and Pearson correlation. The results of the study was found that the hundred and ten digits of the 1st prize were distributed uniformly and The unit digits were a non-uniform distribution (χ2= 27.413, p-value < 0.05). The last 2 digits of the 1st prize, the ten digits were a uniform distribution and The unit digits were a non-uniform distribution (χ2= 17.227 p-value 0. < 0.05), and The five digits were not linearly correlated. The proportion of Triple number, Palindromic number, prime number, and even number of the last 2 digits drawn in the 1st prize is not statistically different from the classic probability but The double number is statistically different from the classic probability (t = 2.194, p-value < 0.05). The expected return on investment in buying 1 lottery ticket for 80 baht will result in a loss of 30.87 baht. It can be concluded that the unit digit of The 1st prize and the last 2 digits is an abnormal distribution of the probabilities.