2022 Introduction to Statistics in Research Mitchell 2nd ed

I N T R O T O R E S E A R C H : D A T A V I S U A L I Z A T I O N & C O M M O N S T A T T E S T S

Cross-tabulation: a technique for comparing data from two or more categorical variables.

Data mining: applying models to extract meaningful knowledge from large volumes of data.

Data visualization: the process of developing appropriate views of aggregate data from multiple dimensions with the intent of gaining a deeper holistic understanding of the data.

Dependent variable: in regression, the variable whose values are supposed to be explained by changes in the other variable (i.e. the hotter the temperature (independent variable) the more swimmers (dependent variable) in your pool).

Discrete variable: Isolated points along a number line. Usually counts of items (like the number of textbooks purchased).

Descriptive statistic: displays characteristics of the location, spread, and shape of data.

Descriptive study : a study that describes or defines a subject, often by creating a profile of a group of problems, people, or events through the collection of data, tabulation of frequencies, or their interaction. The study intends to reveal who, what, when, where, or how much using a univariate hypothesis where the researcher states something about the size, form, distribution, or existence of a variable.

Double-blind, double-blind experiment: neither the subjects nor the people evaluating the subjects know who is in the treatment group and who is in the control group to mitigate the placebo effect.

Double-barreled question: a question that represents so much content that it would be better if separate questions were asked or a question that includes two or more questions that a participant might want to answer differently.

Empirical rule: That a normal distribution has 68% of its observations within one standard deviation of the mean, 95% within two, and 99.7% within three.

Expected value: a predicted value of a variable. To calculate multiply the probability of its occurrence and sum it.

Example of Expected value: A group of (Human Resources) HR specialist are considering additional maternity leave. They conducted a survey asking all HR specialists across several organization to suggest the idea number of additional maternity weeks they should consider. This would be available to parents in the first year beyond the 12 weeks of unpaid leave required by the Medical Leave Act. The HR personnel discussion thread on this additional unpaid maternity leave is summarized here.

Table 35: Example of Expected Value

Essentially, 5% of participants felt one-week additional leave, 18% suggested two weeks, 52% suggested 3 weeks, and 25%

suggested 4 weeks additional. The expected value is 2.97 weeks. (Quiz)

Experiment: In an experiment, the researcher determines who will be in what experimental groups and what the experimental conditions will be.

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