Frequency Distribution and Histogram Development
The following analysis will develop a frequency distribution based on the provided dataset, create a histogram, construct a relative frequency distribution, and develop a relative frequency histogram.
Given Data
The provided data points are:
5, 3, 2, 6, 6,
7, 3, 3, 6, 7,
7, 9, 7, 5, 3,
12, 6, 10, 7, 2,
6, 8, 0, 7, 4
Step 1: Frequency Distribution
First, we will tally the occurrences of each value in the dataset.
Value |
Frequency |
0 |
1 |
1 |
0 |
2 |
3 |
3 |
6 |
4 |
4 |
5 |
7 |
6 |
7 |
7 |
8 |
8 |
3 |
9 |
1 |
10 |
2 |
11 |
0 |
12 |
2 |
Step 2: Histogram
To visualize the frequency distribution, we can create a histogram. Each bar will represent the frequency of each value.
Frequency Histogram:
Value
|
|
| ████████
| ████████
| ████████ ████████
| ████████ ████████
| ████████ ████████
| ████████ ████████
| ████████ ████████
| ████████ ████████
|_______|____|_____|____|_____|____|_____|____
0 2 4 6 8 10 12
Step 3: Relative Frequency Distribution
To create a relative frequency distribution, we calculate the relative frequency for each value by dividing its frequency by the total number of observations.
Total number of observations = 30 (counting all values)
Value |
Frequency |
Relative Frequency |
0 |
1 |
1/30 = 0.033 |
2 |
3 |
3/30 = 0.100 |
3 |
6 |
6/30 = 0.200 |
4 |
4 |
4/30 = 0.133 |
5 |
7 |
7/30 = 0.233 |
6 |
7 |
7/30 = 0.233 |
7 |
8 |
8/30 = 0.267 |
8 |
3 |
3/30 = 0.100 |
9 |
1 |
1/30 = 0.033 |
10 |
2 |
2/30 = 0.067 |
12 |
2 |
2/30 = 0.067 |
Step 4: Relative Frequency Histogram
A relative frequency histogram can be visualized similarly to the frequency histogram, but with the height of each bar representing the relative frequency:
Relative Frequency Histogram:
Value
|
|
| ███████
| ███████
| ███████ ███████
| ███████ ███████
| ███████ ███████
| ███████ ███████
| ███████ ███████
|_______|_____|_____|_____|_____|_____|_____|
0 .1 .2 .3 .4 .5
Grouped Data Frequency Distribution
Assuming you have data for electronic sales for 120 months, using the 2k > n guideline, we can determine the smallest number of groups (k
) to use for constructing a grouped frequency distribution.
Using the formula k=log2(n)k = \log_2(n):
- Here n=120n = 120
- k≈log2(120)≈log10(120)log10(2)≈2.0790.301≈6.9k \approx \log_2(120) \approx \frac{\log_{10}(120)}{\log_{10}(2)} \approx \frac{2.079}{0.301} \approx 6.9
Since k
must be a whole number, we round up to 7. Thus, the smallest number of groups is 7.
Advantages of Relative Frequency Distribution
- Standardization: Relative frequencies allow for comparison across different datasets or distributions regardless of sample size, as they express frequencies as proportions of the total.
- Interpretability: Understanding relative frequencies can be more intuitive for interpreting how significant each category is in relation to the whole dataset.
- Normalization: It helps in normalizing data and understanding patterns when working with different scales and units.
- Data Visualization: When creating visual representations like pie charts or relative frequency histograms, it becomes easier to comprehend the distribution of data.
Overall, the construction of a relative frequency distribution offers valuable insights that can enhance data interpretation and analysis in various fields.