All Flashcards
Define descriptive statistics.
Methods for summarizing and describing the key features of a dataset.
Define inferential statistics.
Methods for making inferences or drawing conclusions about a population based on sample data.
What is the mean?
The average of a dataset, calculated by summing all values and dividing by the number of values.
What is the median?
The middle value in a dataset when the values are ordered from least to greatest.
What is the mode?
The most frequently occurring value in a dataset.
Define standard deviation.
A measure of how much the values in a dataset deviate from the mean.
What is the range?
The difference between the highest and lowest values in a dataset.
Define correlation coefficient.
A measure of the strength and direction of the relationship between two variables, ranging from -1 to +1.
What is a frequency distribution?
Shows how scores fall into different categories.
Define statistical significance.
The likelihood that a result occurred by chance. A statistically significant result is unlikely to have occurred by chance.
How is understanding correlation used in everyday life?
Helps to interpret relationships between events, but avoid assuming causation without further evidence.
How is the concept of standard deviation applied in quality control?
Used to measure the consistency of a manufacturing process; lower SD indicates higher consistency.
How are measures of central tendency used in grading?
Teachers use mean, median, and mode to understand the typical performance of students on exams.
How is statistical significance applied in medical research?
Used to determine if the results of a clinical trial are likely due to the treatment or due to chance.
Explain the difference between descriptive and inferential statistics.
Descriptive statistics describe data, while inferential statistics interpret data to make broader conclusions.
What does a positive correlation indicate?
As one variable increases, the other variable also increases.
What does a negative correlation indicate?
As one variable increases, the other variable decreases.
Explain the importance of understanding correlation vs. causation.
Correlation does not equal causation. Just because two variables are related does not mean one causes the other. Experiments are needed to prove causation.
Describe a normal distribution.
A bell-shaped and symmetrical distribution where most data clusters around the mean.
Describe a positively skewed distribution.
A distribution with a tail extending to the right, where the mean is greater than the median.
Describe a negatively skewed distribution.
A distribution with a tail extending to the left, where the median is greater than the mean.
What does a low standard deviation indicate?
Data points are clustered close to the mean.
What does a high standard deviation indicate?
Data points are more spread out from the mean.
What is the 68% rule in a normal distribution?
68% of the data falls within one standard deviation of the mean.
What is the 95% rule in a normal distribution?
95% of the data falls within two standard deviations of the mean.