Lesson 4- Variables and Hypothesis PDF

**LESSON 4- VARIABLES AND HYPOTHESIS** **Introduction** Important components of research writing are identifying variables and hypotheses, which are essential parts of the study. As the hypothesis gives directions and the variables define the scope and content of the study, these components must b...

**LESSON 4- VARIABLES AND HYPOTHESIS** **Introduction** Important components of research writing are identifying variables and hypotheses, which are essential parts of the study. As the hypothesis gives directions and the variables define the scope and content of the study, these components must be replaced appropriately in the study. Choosing the right variables provides focus on the context of research. **Concepts** **Dependent Variable**\ The variable that depends on other factors that are measured. These variables are expected to change as a result of an experimental manipulation of the independent variable or variables. It is the presumed effect. **Independent Variable**\ The variable that is stable and unaffected by the other variables you are trying to measure. It refers to the condition of an experiment that is systematically manipulated by the investigator. It is the presumed cause. A **control variable** is anything that is held constant or limited in a research study. It's a variable that is not of interest to the [study's objectives](https://www.scribbr.com/research-process/research-objectives/), but is controlled because it could influence the outcomes. **Independent vs dependent vs control variables** **Type of variable** **Definition** **Example (salt tolerance experiment)** ------------------------------------------------- --------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------ Independent variables (aka treatment variables) Variables you manipulate in order to affect the outcome of an experiment. The amount of salt added to each plant's water. Dependent variables (aka response variables) Variables that represent the outcome of the experiment. Any measurement of plant health and growth: in this case, plant height and wilting. Control variables Variables that are held constant throughout the experiment. The temperature and light in the room the plants are kept in, and the volume of water given to each plant. **Meaning of Hypothesis** Hypothesis simply means a mere assumption to be proved or disproved. But for a researcher hypothesis is a formal question that he intends to resolve. It is a testable statement; hypotheses are generally either derived theory of from direct observation of data   **Types of Hypothesis** **Null hypothesis** Null hypothesis is the statement about the parameters, which is usually a hypothesis of no difference and is denoted by Ho. **Alternative Hypothesis** Any hypothesis, which is complementary to the null hypothesis, is called an alternative hypothesis, usually denoted by H1.