Statistics Assignment Example | Topics and Well Written Essays - 750 words - 2

Statistics - Assignment Example For ratio or interval scale data, the median is suitable than the mean if the sample or population size is small and the data is scattered (Cohen 229). The concept is interesting because it identifies ignorance that lead to unnecessary or inaccurate data description that is common in statistical reports. It has informed me of the need for precision in reporting data through selection of a single and suitable descriptive statistics for reporting. Pearson correlation helps in investigating and understanding possible associations, strength of association, and directions of associations between a pair of variables. Investigating the relationship between households’ weekly income and corresponding weekly expenditure is a potential study for the Pearson correlation. In the study, weekly income is the independent variable, X, while weekly expenditure is the dependent variable, Y. A stratified random sampling design is be used to identify participants from different ranges of income and paired data recorded for each household. Area of residence, with the effects of social class, is the basis of stratification and correlation analysis informs data analysis with r and r2 values as the key statistics. A positive r value, such as +0.7, is expected and this shows that household income and income expenditure have a strong positive correlation. This means that increase in the value of one variable leads to corresponding increase in the value of another. The r2 value indicates reliability of the proposed relationship and shows percentage of the data that the relationship explains. In this case, r2 is 0.49 and means that the correlation coefficient explains 49 percent of the analyzed data (Weinberg and Abramowitz 130). T-test for independent samples can be used to investigate effects of training on an organization’s sales representatives. Two groups would be involved in the study. One group, the treatment group, is a sample of 20 sales representatives from a