Probability and Statistics - Midterm 1

(CH1) - What is a frequency distribution table?

A table that displays the frequency of observations in each interval of a sample.

(CH1) - the first thing you should do when trying to make a frequency data table from a sample?

Find the minimum and maximum values of the data set.

(CH1) - How do you create a histogram?

First, you have to do a frequency distribution. Then, you plot the relative frequency for each interval.

(CH1) - A unimodal distribution has:

One peak

(CH1) - A bimodal distribution has:

Two peaks

(CH1) - multimodal distribution has

Multiple peaks

(CH1) - uniform distribution:

Has values that appear with equal frequency

(CH1) - Symmetric distrubution:

Mean = median

(CH1) - If the data is skewed to the left:

The tail is longer on the left side and the median is greater than the mean. Also, this is referred to as negatively skewed.

(CH1) - If the data is skewed to the right:

The tail is longer on the right side and the median is less than the mean. Also, this is referred to as positively skewed.

(CH1) - The peak of a distribution could also be considered as:

The median

(CH1) - Two events can:

Occur at the same time.

(CH1) - Two outcomes can:

Not occur at the same time.

(CH1) - What are the three measures of central tendency?

Mean (average), mode (most frequent value), and median (middlemost value)

(CH1) - What is a better measure of central tendency: mean or median? Why?

Median is a better measure of central tendency, because the mean is greatly influenced by outliers.

(CH1) - What is a measure of variation?

A measurement that provides info about the spread of data.

(CH1) - How is a reorganized data set denoted?

X1, which is usually referred to as the first point in the data set, is marked as X(1), to indicate an ordered data set.

(CH1) - What would make a sample have a larger standard deviation?

(CH1) - The sample has a larger interquartile range and has outliers.

(CH1) - Describe how to create a box plot.

First, find the min and max of the data set after ordering the data set, which will be the two closed dots on the plot. Then, find out Q1 and Q3, which will be the beginning and end of the box. After that, find the median/Q2 of the data. Lastly, CHECK FOR OUTLIERS and place them on the plot as HOLLOW HOLES!

(CH2 ) - The event consisting of all outcomes that are contained in A or B or both is known as:

The union, denoted as a U.

(CH2 ) - The event consisting of outcomes that are in both A and B is known as:

The intersection, denoted as n.

(CH2 ) - The event consisting of outcomes that are in not in event A is known as:

The complement, denoted as A^c

If two events have no outcomes in common, then the events are:

Mutually exclusive/disjoint.