Hypothesis Examples: Different Types in Science and Research

A hypothesis is a stepping stone to proving a theory. For a hypothesis to be considered a scientific hypothesis, it must be proven through the scientific method. Like anything else in life, there are many paths to take to get to the same ending, and there are numerous types of hypotheses that can be employed when seeking to prove a new theory. Additionally, there are many hypothesis examples that can be applied to solve the problem at hand.

Woman in Bed Examples of Hypothesis Woman in Bed Examples of Hypothesis

Parts of a Hypothesis: Independent and Dependent Variables

Before diving into hypothesis examples, you must take a moment to understand independent and dependent variables. Simply put, an independent variable is the cause, and the dependent variable is the effect. The independent variable can be changed, whereas the dependent variable is what you're watching for a change. For example:

How does the amount of makeup one applies affect how clear their skin is?

Here, the independent variable is the makeup, and the dependent variable is the skin. The variables are important because they help determine the cause and effect. In this example, the hypothesis could be: the amount of makeup one wears correlates to how clear their skin is. Therefore, this hypothesis must be tested before it can be proven correct.

Types of Hypotheses

The most common forms of hypotheses are:

  • Simple Hypothesis

  • Complex Hypothesis

  • Null Hypothesis

  • Alternative Hypothesis

  • Logical Hypothesis

  • Empirical Hypothesis

  • Statistical Hypothesis

See how these types of hypotheses are created through examples.

Simple Hypothesis Examples

A simple hypothesis predicts the relationship between two variables: the independent variable and the dependent variable. This relationship is demonstrated through these examples.

  • Drinking sugary drinks daily leads to being overweight.

  • Smoking cigarettes daily leads to lung cancer.

  • Getting at least 8 hours of sleep can make people more alert.

These things are not always true, but they are generally true.

Complex Hypothesis Examples

A complex hypothesis has a relationship between variables. However, it’s a relationship between two or more independent variables and two or more dependent variables. You can follow these examples to get a better understanding of a complex hypothesis.

Based on existing data, we can deduce that:

  • Adults who 1) drink sugary beverages on a daily basis and 2) have a family history of health issues are more likely to 1) become overweight and 2) develop diabetes or other health issues.

  • Individuals that 1) smoke cigarettes and 2) live in large cities are more likely than others to have 1) respiratory problems and 2) an increased risk of cancer.

  • Individuals who 1) get an average of eight or more hours of sleep and 2) have a balanced diet and schedule are more likely to 1) be alert during the day and 2) have more energy.


Null Hypothesis Examples

A null hypothesis, denoted by H0, is formed when a researcher believes there is no relationship between the two variables or a lack of information to state a scientific hypothesis. This is something to attempt to disprove or discredit.

  • There is no significant change in a person’s health during the times when they drink green tea only or root beer only.

  • There is no significant change in an individual’s work habits whether they get eight hours or nine hours of sleep.

  • There is no significant change in the growth of a plant if one uses distilled water only or vitamin-rich water.

Alternative Hypothesis Examples

This is where the alternative hypothesis, denoted by H1, enters the scene. An alternative hypothesis is a claim that is contradictory to the null hypothesis. In an attempt to disprove a null hypothesis, researchers will seek to discover an alternative hypothesis.

  • A person’s health improves during the times when they drink green tea only, as opposed to root beer only.

  • Work habits improve during the times when one gets 8 hours of sleep only, as opposed to 9 hours of sleep only.

  • The growth of the plant improved during the times when it received vitamin-rich water only, as opposed to distilled water only.

Logical Hypothesis Examples

A logical hypothesis is a proposed explanation possessing limited evidence. Generally, you want to turn a logical hypothesis into an empirical hypothesis, putting your theories or postulations to the test. In reference to these examples, there is currently no evidence to support these hypotheses. However, we can form a hypothesis based on the data available to us to draw a logical conclusion.

  • Cacti experience more successful growth rates than tulips on Mars.

  • Beings from Mars would not be able to breathe the air in the atmosphere of the Earth.

  • Creatures found in the bottom of the ocean use aerobic respiration rather than anaerobic respiration.


Empirical Hypothesis Examples

An empirical hypothesis, or working hypothesis, comes to life when a theory is being put to the test, using observation and experiment. It's no longer just an idea or notion. Rather, it is going through trial and error and perhaps changing around those independent variables.

  • Roses watered with liquid Vitamin B grow faster than roses watered with liquid Vitamin E.

  • Women taking vitamin E grow hair faster than those taking vitamin K.

  • Thirsty rats find their way through a maze quicker if there is water at the end of the maze.

In these examples, trial and error is leading to a series of findings. The results of these experiments can all be observed and proven over time.

Statistical Hypothesis Examples

A statistical hypothesis is an examination of a portion of a population or statistical model. In this type of analysis, you use statistical information from an area. For example, if you wanted to conduct a study on the life expectancy of people from Savannah, you would want to examine every single resident of Savannah. This is not practical. Therefore, you would conduct your research using a statistical hypothesis or a sample of the Savannian population.

  • 50% of the Savannah population lives beyond the age of 70.

  • 80% of the U.S. population gets a divorce because of irreconcilable differences.

  • 45% of the poor in the U.S. are illiterate.

Parameters of a Good Hypothesis

For a hypothesis to be sound, hold tight to these tips.


Step 1: Ask Yourself Questions

Define the independent and dependent variables very specifically, and don't take on more than you can handle. Keep yourself laser-focused on one specific cause-and-effect theory.

Step 2: Be Logical and Use Precise Language

Keep your language clean and simple. State your hypothesis as concisely and to the point as possible. A hypothesis is usually written in a form where it proposes that, if something is done, then something else will occur. Usually, you don't want to state a hypothesis as a question. You believe in something, and you're seeking to prove it. For example:

If I raise the temperature of a cup of water, then the amount of sugar that can be dissolved in it will be increased.

Step 3: Make Sure Your Hypothesis Is Testable

Any hypothesis will need proof. Your audience will have to see evidence and reason to believe your statement. For example, I may want to drink root beer all day, not green tea. If you're going to make me change my ways, I need some sound reasoning and experimental proof — perhaps case studies of others who lost weight, cleared up their skin and had a marked improvement in their immunity by drinking green tea.

Applying Your Hypothesis

Scientists can really change the world with their hypotheses and findings. To improve the world we live in, all it takes is an initial hypothesis that is well-stated, founded in truth and that can withstand extensive research and experimentation. Seek out your independent and dependent variables, and go on out there and make this world a better place. Now it’s time to learn about scientific method examples and applying it to your own research.