data handling descriptive statistics and computation

Measures of central tendency refer to any statistic that gives an indication of the average or midway value in a data set.

a. The mean indicates what a researcher would expect to find if they were to replicate the procedure of a given study.

The mean is more likely than other measures of central tendency to provide a representative score.

False. The mean can not be used with all data sets as it is sensitive to extreme scores (outliers).

The median calculates the middle value of a data set (the positional average).

If there are two middles values the median is calculated by adding the two middle values and dividing the total by 2.

True. The median is the best measure of central tendency when dealing with qualitative data. This is appropriate where ranking of categories or themes is used instead of measurement or counting.

c. The median is not a representative average as it does not include all of the data in its calculations.

The mode calculates the most frequently occurring score in a data set.

c. Some data sets may have strange modes is not a feature of the mode.

True. A strength of the mode is that it is not affected by extreme values (outliers).

A data set may include two modes which blurs the meaning of the data, making it difficult for the researcher to form conclusions.

Measures of dispersion calculate the spread of scores in terms of how distant they are from the mean or median.

The range describes the difference between the lowest and the highest scores in a data set.

True. A strength of the range is that it is simple and easy to calculate.

b. The range provides no information as to all of the other scores in the **data set which means that it lacks validity. This is because it does not indicate the degree of variation **from the mean.

Standard deviation calculates how a set of scores deviates from the mean. It provides insight into how clustered or spread out the scores are from the mean.

A low standard deviation indicates that the scores are clustered tightly around the mean, which indicates the reliability of the data set.

False. A limitation of standard deviation is that it is skewed by outliers.

a. Standard deviation provides information as to how the scores are distributed across a data set. This is a strength as it can indicate to what extent the data set is reliable and consistent.