Appendix B Flashcards
What are descriptive statistics?
Descriptive statistics are used to describe and summarize data.
What are inferential statistics?
Inferential statistics are used to draw conclusions about research data.
What is an ungrouped frequency distribution?
It is a count of the number of times each specific data point or score appears in a data set.
What is a grouped frequency distribution?
It is a count of the number of times specific data points fall into a range of values in a data set.
What is a histogram?
A histogram is a bar chart showing the number of times specific data points fall into a range of values in a data set.
What is a frequency polygon?
A frequency polygon is a line graph depicting a grouped frequency distribution, created by connecting the midpoints of each class of data.
What are the three most common measures of central tendency?
Mean, median, and mode
How is the mean calculated?
The mean is the sum of all values in a data set divided by the number of values.
What is the median?
The median is the middle value in an ordered data set.
What is the mode?
The mode is the most frequent or most common value in a data set.
What are measures of variability?
Measures that tell how different the values are within a data set, such as range, variance, and standard deviation.
What is the range?
The range is the difference between the smallest and largest values in a data set.
What is variance?
Variance is the average of the squared deviations from the mean, indicating how spread out the values are.
What is standard deviation?
Standard deviation is the square root of the variance, providing a measure of variability in the same metric as the original data.
What is a normal distribution?
A normal distribution is a symmetrical, bell-shaped distribution where most scores cluster around the middle.
What is a positively skewed distribution?
A distribution where most values occur at the lower end of the scale, and the tail extends to the right.
What is a negatively skewed distribution?
A distribution where most values occur at the upper end of the scale, and the tail extends to the left.
What is a scatterplot?
A scatterplot is a graph that shows the relationship between two variables by plotting data points on two axes.
What is the Pearson product-moment correlation coefficient (r)?
It is a statistic that indicates the degree of relationship between two variables, ranging from −1 to +1.
What is hypothesis testing?
Hypothesis testing involves testing claims about a population using a sample, typically by comparing experimental and control groups.
What is a null hypothesis?
The null hypothesis asserts that there is no difference between groups or variables being studied in a population.
What is an alternative hypothesis?
The alternative hypothesis asserts that there is a difference between groups or variables in the population.
What is a significance level in hypothesis testing?
It is the level of risk researchers are willing to take when making conclusions, often set at p < 0.05 or p < 0.01.
What is effect size?
Effect size is a standardized measure that reflects the degree of relationship or the size of the difference between variables.
What is Cohen’s d?
Cohen’s d is a standardized effect size that measures the difference between two population means.
What is an ungrouped frequency distribution table used for?
It displays how many times each unique score occurs in a data set.
What is a deviation score?
A deviation score is the difference between an individual score and the mean of the data set.
What is covariance?
Covariance is a measure of how two variables change together, calculated as the sum of the products of deviation scores.
What does a sampling distribution represent?
A sampling distribution represents the distribution of a statistic (e.g., mean) from many samples taken from a population.
What is the coefficient of determination (r²)?
It is the square of the Pearson correlation coefficient and indicates how much of the variability in one variable can be predicted from the other.
How does a positively skewed distribution affect the mean, median, and mode?
The mean is greater than the median, which is greater than the mode.
How does a negatively skewed distribution affect the mean, median, and mode?
The mode is greater than the median, which is greater than the mean.
What is a random sample?
A sample where each member of the population has an equal chance of being selected.
