Histogram

A histogram represents frequency distribution using graphs. Here, the data is grouped into specific ranges to make it easier to represent. Think of it like a bar graph, with the x-axis representing numerical ranges and the y-axis denoting frequency. It is used for data collection and analysis. 

Here are a few scenarios where we use histograms for data analysis. 

• Analyzing the data distribution means checking whether the data is distributed correctly or not. 

• A histogram helps track changes that occur in a process over time, thereby showing us whether the process remains the same or keeps changing.

• A histogram is used to compare two or more process.

• A histogram is used to analyze the customer requirements of a process.

In this section, let’s learn about types of histograms. Based on the type of frequency, histograms can be classified into:

• Normal Distribution

• Skewed Distribution

• Double-Peaked Distribution

• Plateau Distribution

• Edge Peak Distribution

• Comb Distribution

• Truncated Distribution

• Dog Food Distribution

Normal Distribution

A normal distribution is the common pattern seen in histograms. The normal distribution is also known as a bell-shaped histogram because of its curve, which has a single peak at a specific time interval.  

Skewed Distribution

The skewed distribution is skewed in one direction, either to the right or left. The skew to the right is a right-skewed distribution, and the one to the left is a left-skewed distribution.

Double-Peaked Distribution

Double-peaked distribution is also known as bimodal; as the name suggests, it has two peaks. It is the outcome of two processes with different distributions in one set of data. 

Plateau Distribution

Plateau distribution is the combination of many processes in one data set.
 

Edge Peak Distribution

Edge peak distribution looks similar to the normal distribution, but has one large peak in the tail.
 

Comb Distribution

Comb distribution has alternative large and small bins; it can be because either the data is rounded off or incorrectly constructed. 
 

Truncated Distribution

Truncated distribution is also known as heart-cut distribution. It is also similar to a normal distribution with no tail.

Dog Food Distribution

Dog food distribution refers to unevenly distributed data where most values cluster in one group, leaving very few in others.

In this section, let’s learn how to make a histogram. Follow these steps to draw a histogram. 

Step 1: Collect the data and categorize it into groups based on the interval. The interval should be of the same length. 

Step 2: Make a table and arrange the data by listing each interval with the number of values that fall within it.

Step 3: The y-axis must represent the frequency(f), while the x-axis will represent the intervals. So, label the title on both axes. Also, label the intervals and frequencies on both x and y-axis. 

Step 4: Draw the bars based on the table created, that is, each bar should indicate the correct frequency. 

We know that there are many similarities between histograms and bar graphs. So, in this section, let’s learn the difference between a histogram and a bar graph. 
 

Histograms are used in different fields to compare data, spot trends, identify patterns, and so on. So, let’s learn a few applications of histograms. 

• In business, histograms are used to compare data, analyze sales, product quality, and so on.

• To identify the outcome of a common process, we use a histogram; it does not take much time to understand the data given in a histogram. 

• A histogram is used to analyze the disease incidence, treatment outcome, patient's history, etc. 

Tips and tricks are always interesting, and they can help students master any skill. So, let’s see a few tips and tricks to master histogram. 

• Understand the concept and types of histogram clearly.

• Label the axis carefully. In a histogram, the x-axis represents continuous data, and the y-axis represents the frequency. 

• Remember that there are no gaps between the bars in a histogram.