Statistics fall review

Front

What does a correlation coefficient (r) of 0.89 indicate about the relationship between two variables?

Back

A correlation coefficient (r) of 0.89 indicates a strong positive relationship, meaning that as one variable increases, the other variable tends to also increase.

Front

What are resistant measures in statistics?

Back

Resistant measures are statistical measures that are not significantly affected by outliers. Examples include the median and the interquartile range (IQR).

Front

How do you calculate the probability of independent events?

Back

For independent events, the probability of both events occurring is the product of their individual probabilities. For example, if the probability of winning a match is 0.6, the probability of losing two matches in a row is 0.4 * 0.4 = 0.16.

Front

What is the interquartile range (IQR)?

Back

The interquartile range (IQR) is a measure of statistical dispersion, calculated as the difference between the third quartile (Q3) and the first quartile (Q1). It represents the range of the middle 50% of the data.

Front

When is the median a better measure of central tendency than the mean?

Back

The median is a better measure of central tendency than the mean when the data set contains outliers or is skewed, as it is not affected by extreme values.

Front

What is the difference between the mean and the median?

Back

The mean is the average of all data points, while the median is the middle value when the data points are arranged in order. The mean can be influenced by outliers, whereas the median is not.

Front

What is a probability model?

Back

A probability model is a mathematical representation of a random phenomenon, describing the likelihood of different outcomes. It assigns probabilities to each possible outcome.

Front

How do you interpret a probability of 0.20 in a probability model?

Back

A probability of 0.20 means that there is a 20% chance of the event occurring. In the context of raffle tickets, it indicates that 20% of customers are expected to buy 3 tickets.

Front

What is the role of the standard deviation in statistics?

Back

The standard deviation measures the amount of variation or dispersion in a set of values. A low standard deviation indicates that the values tend to be close to the mean, while a high standard deviation indicates more spread out values.

Front

What does it mean for two events to be independent?

Back

Two events are independent if the occurrence of one event does not affect the probability of the other event occurring.