Units together Flashcards
What is the role of statistics in the development of knowledge?
Statistics is present wherever knowledge is developed.
What are the two main branches of research mentioned in the slides?
Qualitative and quantitative research.
What are the key steps in a typical research process?
The key steps are research question, documentation, hypothesis formulation, study design, data collection, data analysis, and interpretation of results.
Define the term ‘population’ in the context of data analysis.
Population refers to all the elements that share the characteristic under study, such as people, animals, institutions, or cities.
What is a ‘sample,’ and why is it important that it be representative?
A sample is a subset of the total elements from the population. It must be representative in size and sampling methods to allow for generalizable conclusions.
What are ‘units of analysis’?
Units of analysis are the elements between which some quality is compared, often subjects or individuals.
What is the difference between a parameter and a statistic?
Parameters are values representing quantitative properties of a population, denoted by Greek letters, while statistics represent the same for a sample, denoted by Latin letters.
What are the two main areas of statistics?
Descriptive statistics and inferential statistics.
What is the goal of descriptive statistics?
The goal is to summarize a set of information to interpret and draw conclusions, often using graphs, percentages, and means.
What is the purpose of inferential statistics?
The goal is to estimate, predict, or generalize conclusions about a population based on sample data using probability calculations.
What is a variable in data analysis?
A variable is a feature of the units of analysis that can change or vary between people, over time, or in different situations.
What is a constant?
A constant is a modality or value shared by all the units of analysis, the opposite of a variable.
What are independent and dependent variables?
Independent variables are proposed causes or predictors, while dependent variables are proposed results or outcomes.
How are variables notated in data analysis?
Variables are notated with Latin alphabet letters such as X, Y, U, or V.
Why are variable values coded numerically for data analysis?
For data analysis, variable values are always coded numerically.
What two properties must be ensured when constructing categories for variables?
Mutual exclusion (each category excludes others) and exhaustiveness (all values are covered).
What are the three main types of variables?
Qualitative, quasi-quantitative (ordinal), and quantitative.
What are the two subtypes of quantitative variables?
Continuous (with intermediate values) and discrete (no intermediate values).
What are the four levels of measurement scales for variables?
Nominal, ordinal, interval, and ratio.
What is a nominal scale, and what kind of variables does it apply to?
A nominal scale applies to qualitative variables, with arbitrarily assigned numbers acting as labels. The only association between categories is equal or unequal.
What is an ordinal scale, and what is its key characteristic?
An ordinal scale applies to quasi-quantitative variables, and its key characteristic is that it reflects the order among categories but not the magnitude of the difference between categories.
What is an interval scale, and what mathematical operations are possible with it?
An interval scale applies to quantitative variables, with equal intervals between numbers, allowing for addition and subtraction, but without a true zero point.
What is a ratio scale, and what makes it different from an interval scale?
A ratio scale applies to quantitative variables with a non-arbitrary zero point, allowing for all mathematical properties (addition, subtraction, multiplication, and division).
What does univariate descriptive statistics focus on?
It focuses on the summarized description and analysis of a single variable.
What are the key elements of a frequency distribution?
Absolute frequency, relative frequency, percentage, cumulative absolute frequency, cumulative relative frequency, and cumulative percentage.
What types of graphs are used to represent frequency distributions?
Cyclograms/pie charts, bar charts, frequency polygons, histograms, and stem-and-leaf diagrams.
What are the four properties that characterize the shape of a frequency distribution?
Central tendency, variability, skewness, and kurtosis.
What are measures of position, and what do they indicate?
Measures of position indicate where a score is located in the distribution compared to the rest of the observed values and include quartiles, deciles, and percentiles.
What are measures of central tendency and how do they help?
They represent the average magnitude of all observed values of the variable, establishing a middle point or point of balance, and they summarize the characteristics of a variable and allow to make some comparisons.
What are the most common measures of central tendency?
The mode, median, and mean.
