Grouped Frequency Distribution Table, Grouped Frequency Table, Sample, Distribution
The key terms in these Statistic chapters include Grouped Frequency Distribution Table, Grouped Frequency Table, Frequency Distribution Table, Sample, Distribution, Scale of Measurement, Frequency Distribution, Interval, Population, Mean, Standard Deviation, Z-Score. Homework STATS.
Describe grouped frequency table. Sig?
Scores or values grouped into intervals
For each interval, indicate frequency or number of scores
Useful for large numbers of groups
Describe frequency distribution. Sig?
Organized tabulation of number of individuals or scores located in each category on scale of measurement
Can be organized in table or graph
Can be grouped or ungrouped
Helps see how scores are distributed
How to make a frequency distribution table?
Put down label for each group, then put down the frequency of each group in a table
Sum of F will be total number of samples
Sum of X will be total number of nights out, using given example (7×1+6×2+5×2…)
Relate a receipt to a frequency distribution table.
Sum of F is number of items purchased
Sum of X is total money, sum of all scores
F(X) is the quantity
X is the money for each individual item
Describe grouped frequency table. Sig?
Scores or values grouped into intervals
For each interval, indicate frequency or number of scores
Useful for large numbers of groups
What would be an example of where I’d use a grouped frequency table?
List of grades
Range of 10 points for each X
Number of iterations for each group in f(X)
No categories are skipped
When should I use grouped or ungrouped freq distrib?
When there are more than 10, use grouped
If displaying time or money, perhaps grouped good even for small number of samples
Make the data easy to interpret
For a set of scores ranging from 68 to 61, you should use a grouped frequency distribution table instead of an ungrouped (regular) frequency distribution table. True or false?
False
For the data in the table below, what is the sum of X (sigma X)?
X f(X)
4 1
3 2
2 4
1 2
20
Describe frequency distribution. Sig?
Organized tabulation of number of individuals or scores located in each category on scale of measurement
Can be organized in table or graph
Can be grouped or ungrouped
Helps see how scores are distributed
How to make a frequency distribution table?
Put down label for each group, then put down the frequency of each group in a table
Sum of F will be total number of samples
Sum of X will be total number of nights out, using given example (7×1+6×2+5×2…)
Relate a receipt to a frequency distribution table.
Sum of F is number of items purchased
Sum of X is total money, sum of all scores
F(X) is the quantity
X is the money for each individual item
What is the sum of X (sigma X)?
X f(X)
5 2
4 4
3 1
2 3
35
How many individuals are in this data set?
X f(X)
5 2
4 4
3 1
2 3
10
You should use a grouped frequency distribution table whenever there are more than 15 or 20 total scores or individuals in the group.
False, you may be able to put them in a small number of groups
There is enough information in a grouped frequency distribution table to obtain a complete listing of the original set of scores.
False
What are proportions? Percentages? Sig?
Proportion is frequency divided by total number of frequencies, (p = f/N)
Percentage = p * 100
Helps understand distribution of samples
What are cumulative frequencies? Cumulative percent? Sig?
Freq: continue adding the frequencies as you move up the list
Percent: take percent of each group and then add as you move up the list
Helps understand distribution of data
Example question in video Frequency Distribution Options
For a set of scores ranging from 68 to 61, you should use a grouped frequency distribution table instead of an ungrouped (regular) frequency distribution table.
False
For the data in the table below, what is the sum of X (sigma X)?
X f(X)
4 1
3 2
2 4
1 2
20
For the following data what score corresponds to the cumulative percentage of 60% (i.e., 60th percentile)?
X f(X)
7 4
6 6
5 7
4 5
5
The box plot below depicts the median number of hours a population of N = 12 students reported studying for their first exam within a class. Which statement below is not true based on the box plot?
The interquartile range is 5.
A sample has M = 71 and s = 3. In this sample, what is the X value corresponding to z = +1.33?
X = 75
If an entire population with µ = 60 and σ = 8 is transformed into z-scores, then the distribution of z-scores will have a mean of _____ and a standard deviation of _____.
µ = 0; σ = 1.
A population of scores has µ = 10 and σ = 2. If every score in the population is multiplied by 4, then what are the new values for the mean and standard deviation?
µ = 40 and σ = 8
In order to determine if 10 points below the mean on an exam is an extreme negative score, the _____ needs to be known.
Standard deviation
2% of scores fall between the z scores ________ and ________.
2;3
In a STANDARD NORMAL DISTRIBUTION, approximately ________% of scores fall within 2 standard deviations from the mean
96
A z-score distribution ________ has a mean of ________.
Always; 0