RESEARCH COURSE WORK Essay Example | Topics and Well Written Essays - 2250 words

RESEARCH COURSE WORK - Essay Example Also, as far as population distributions are concerned, non-parametric tests make no assumptions about the shape of these distributions, nor do they assume that the two populations have equal amounts of variability (Miller, 2006). Correlation and Regression A correlation is a numerical value that describes and measures the characteristics of the relationship between two variables. Typically, correlation measures the direction of the relationship, whether positive (direct) or negative (inverse); the type of the relationship, whether, linear, exponential, quadratic, etc.; and, the extent of relationship, that is, correlation close to 1 or -1 indicates a strong relationship while correlation close to zero indicates the minimality of the relationship. If the relationship is linear, then regression gives the linear equation that best predicts the relationship between the independent and dependent variables (Gravetter & Wallnau, 2008). Measures of central tendency The mean, median and mode of a data set measure central tendency. The mean is typically the â€Å"average† value of the data set, taken by summing up all the data points and dividing the sum by the total sample size. The mean is used when the distribution is somehow evenly distributed, without the presence of extreme values. The mode is the most frequent value in the data set, and is most commonly used when the data is made up of categorical or nominal values. The median is the â€Å"middle value† or the score that divides the distribution in half so that 50% of the values lie below or at the median (Bluman, 2004). When a distribution is symmetrical, the right-hand side of the graph will be a mirror image of the left-hand side. In this case, there is only one mode and it is equal to the mean and the median. Skewed distributions, on the other hand, are lopsided towards one side. Positively skewed distributions peak at the left where the mode is, the median to the right of the mode and the mean to the right of the median. In negatively skewed distributions peaked to the right where the mode is, the median to the left of the mode, and the mean to the left of the median (Gravetter & Wallnau, 2008). The meaning of â€Å"Statistical Significance† Statistical significance is basically the level of risk that one is willing to take in rejecting a true null hypothesis. For example, when testing the equality of the means of two data sets at 1% or .01 level of significance, it means that on any test of the null hypothesis, there is a 1% chance of rejecting the null hypothesis and thus concluding that there is a difference in the means when there is no difference at all (Miller, 2006). Part B. The research topic The data set extracted from Brainmass.com was gathered to conduct research on the housing of a neighborhood that encompasses 5 townships. Using the data gathered from 100 housing properties, the researcher wants to find out the relationship of the characteristics of th e real estate property to its market value. Furthermore, the researcher wants to find out which among the variables have the greatest effect on the market price in order to come up with a mathematical model that will forecast the market value of a property given the values of the independent variables. The research variables The following variables were used in this data set: Price The variable â€Å"Price† refers to the current price or market value of the housing property, measured in thousands of US dollars. This variable is treated