AP Stat Unit 1 & 2 Review

Front

What is the importance of starting the vertical scale at 0 in a bar graph?

Back

Starting the vertical scale at 0 prevents distortion of the data representation, ensuring that comparisons between different categories are accurate and not misleading.

Front

What does it mean for a distribution to be approximately normal?

Back

A distribution is approximately normal if it follows a bell-shaped curve, where most of the data points cluster around the mean, and the probabilities for values further away from the mean taper off symmetrically.

Front

How do you calculate the 75th percentile in a normal distribution?

Back

To find the 75th percentile, you can use the mean and standard deviation to determine the z-score that corresponds to the 75th percentile (approximately 0.674) and then use the formula: X = mean + (z * standard deviation).

Front

What is the formula for calculating the proportion of data below a certain value in a normal distribution?

Back

Use the z-score formula: z = (X - mean) / standard deviation, then refer to the standard normal distribution table to find the proportion.

Front

What is the 1.5 x IQR rule for identifying outliers?

Back

An outlier is defined as a data point that is less than Q1 - 1.5 * IQR or greater than Q3 + 1.5 * IQR, where IQR is the interquartile range (Q3 - Q1).

Front

What is a back-to-back stem plot?

Back

A back-to-back stem plot is a graphical representation that displays two related distributions side by side, allowing for easy comparison of their shapes and central tendencies.

Front

What does the term 'quartile' refer to in statistics?

Back

A quartile is a type of quantile that divides a data set into four equal parts, with Q1 being the first quartile (25th percentile), Q2 the median (50th percentile), and Q3 the third quartile (75th percentile).

Front

How do you interpret the mean and median in a data set?

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 affected by outliers, while the median is more robust.

Front

What is the significance of the standard deviation in a data set?

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 is the difference between a bar graph and a pie chart?

Back

A bar graph displays categorical data with rectangular bars representing the frequency or proportion of each category, while a pie chart shows the relative proportions of parts to a whole as slices of a circle.