Stat Ch2.1-2.3 quiz notes

uniform

when all the bars are equal height

Organizing the data into a frequency distribution can make patterns within the data more evident

What are some benefits of representing data sets using frequency​ distributions?

1,1,5,5,5,6,6

Choose the data set where the median and mode of the set are equal.

2,2,8,8

Choose the data set whose mean is not equal to a value in the set.

TRUE

Determine whether the statement is true or false. If it is​ false, rewrite it as a true statement. A data set can have the same​ mean, median, and mode.

The statement is false. An ogive is a graph that displays cumulative frequencies.

Determine whether the statement is true or false. If it is​ false, rewrite it as a true statement. An ogive is a graph that displays relative frequencies.

class width= 13 choose the correct lower class limits: 12​, 25​, 38​, 51, 64​, 77 correct upper class limits: 24, 37, 50, 63, 76, 89

Use the given minimum and maximum data​ entries, and the number of​ classes, to find the class​ width, the lower class​ limits, and the upper class limits. minimum=12​, maximum=88, 6 classes

skewed right

when the bars decrease as you move to the right

It can be easier to identify patterns of a data set by looking at a graph of the frequency distribution

What are some benefits of using graphs of frequency​ distributions?

Class limits are the least and greatest numbers that can belong to the class. Class boundaries are the numbers that separate classes without forming gaps between them. For integer​ data, the corresponding class limits and class boundaries differ by 0.5.

What is the difference between class limits and class​ boundaries?

class width= 15 lower class limits: 13, 28, 43, 58, 73, 88, 103, 118 upper class limits: 27, 42, 57, 72, 87, 102, 117, 132

Use the given minimum and maximum data​ entries, and the number of​ classes, to find the class​ width, the lower class​ limits, and the upper class limits. minimum=13​, maximum=128​, 8 classes

The value that lies in the middle of the data when the data set is ordered.

Construct the described data set. The entries in the data set cannot all be the same. The median and the mode are the same.

mode

The data entry that occurs with the greatest frequency.

yes There is no mode

The length​ (in words) of seven articles from a particular newspaper are listed below. Find the​ mean, median, and mode of the​ data, if possible. If any of these measures cannot be found or a measure does not represent the center of the​ data, explain why. 816 1153 1225 1278 1369 1123 1277 does median represent center of data? Find the mode of the word counts.

mean: 9.2 yes median: 9 yes mode: 8 The​ mode(s) does​ (do) not represent the center because it​ (one) is the smallest data value.

The number of credits being taken by a sample of 13​ full-time college students are listed below. Find the​ mean, median, and mode of the​ data, if possible. If any measure cannot be found or does not represent the center of the​ data, explain why. 9 11 12 12 9 8 8 8 10 8 8 8 9 find the mean does it represent the center of the data? find median does it represent center? find mode does it represent center?

yes Mode: 43, yes it represents center

The tuition and fees​ (in thousands of​ dollars) for the top 14 universities in a recent year are listed below. Find the​ mean, median, and mode of the​ data, if possible. If any of these measures cannot be found or a measure does not represent the center of the​ data, explain why. 41 45 39 43 43 42 40 44 47 43 43 45 46 43 does the median represent the center of data? find the mode of the costs.. does it represent center?

Both plots can be used to determine specific data entries Both plots show how data are distributed. Both plots can be used to identify unusual data values

In terms of displaying​ data, how is a​ stem-and-leaf plot similar to a dot​ plot?

7

A data set includes the entries 2​, 4​, 5​, 7, 7​, and 10. Complete the data set with an entry between 1 and 10 so that the median and mode of the set are equal.

The sum of the data entries divided by the number of entries.

Construct the described data set. The entries in the data set cannot all be the same. The mean is not representative of a typical number in the data set. What is the definition of​ mean?

If percentages are​ used, the sum should be​ 100%. If proportions are​ used, the sum should be 1.

After constructing a relative frequency distribution summarizing IQ scores of college​ students, what should be the sum of the relative​ frequencies?

False. In a frequency​ distribution, the class width is the distance between the lower or upper limits of consecutive classes.

Determine whether the statement is true or false. If it is​ false, rewrite it as a true statement. In a frequency​ distribution, the class width is the distance between the lower and upper limits of a class.