Essay on Homework 1

Strengths to this design are it allows the development of questions for further studies. It allows for testing of the expected relationships between the variables. It also allows for drawing conclusions about the relationship.

Scientific method is used to solve empirical problems and discover empirical truth in an empirical pattern. The scientific method involves several steps, the first step is observing or asking question, second step is forming a hypothesis, third step is testing the hypothesis or experimenting, fourth step is confirm or disconfirm the hypothesis. In the simplest terms, scientific method is a process of trial and error. To give a concise example consider vehicle repair. Every weekend handyman, or every high school student with a passing interest in autos knows about the method of trial and error. If your car is starting to run poorly, and you take matters into your own hands in an attempt to fix it. The first step is to guess the nature of the problem for example faulty emission or low brake fluid. Acting on your instinct, you proceed to exchange a part, adjust a setting, or replace a fluid, and then see if the car runs better. If your initial guess is incorrect and the car is not improved, you revise your guess, make another adjustment, and once again test the car. With patience and enough guesses, this process will often result in an operable car. However, depending on one's

The scientific method is a process used to prove or disprove a hypothesis through experimentation and analysis. The steps necessary include Asking a question and/or observation, Forming a hypothesis, Test the hypothesis, Analyze the results, Draw a conclusion, and Publish the findings.

4. In a well-designed study, what does it mean to say there is a statistically significant difference between groups?

The first section talks about first establishing the cause and effect relationship that you are going to be testing. By determining the cause and effect relationship that you intend to test, so that an outsider can test its validity based on your intended cause and effect, and the realized cause and effect. The following section talks about single groups, more in particular about threats of a single group to your cause and effect. It talks about 6 threats to single groups, including history threats, maturation threats, testing threats, instrumentation threats, mortality threats and regression threats, and gives good examples on how these threats may appear in your data. It then moves on to talk about multiple group threats, and how it relates to selection bias or selection threats. It describes and gives concrete examples of six types of multiple group threats, which include including selection-history threats, selection-maturation threats, selection-testing threats, selecting-instrumentation threats, selection-mortality threats and selection-regression threats. Lastly, this section talks about social interaction threats as it relates to validity. It identifies and gives examples for four social threats, which are diffusion or imitation treatment, compensatory rivalry, resentful demoralization, and compensatory equalization of treatment. The reason that I

3.     What are the advantages and disadvantages of an experimental design in an educational study?

Determine which of the following assignment statements are valid. For each invalid statement, explain why it is invalid. Assume that each statement immediately follows the above variable declarations.

The scientific method is a tool that enables a person to seek out new knowledge, or correct and integrate new knowledge. It is composed of eight individual steps: which start out with defining a question, gathering information and resources, form an explanatory hypothesis, test the hypothesis by performing an experiment and collecting data in a reproducible manner, analyze the data, interpret the data and draw conclusions that serve as a starting point for new hypothesis, publish results, and ends with a retest. The steps can be grouped into four different essential elements: operation, observation, model, and utility function.

The experiment is an example of a matched pairs design, which is used when an experiment has two treatment conditions and the subjects are paired based on a blocking variable, and within each pair the subjects are assigned to a different treatment randomly. There were a total of 72 children within this lab

     In conclusion, scientific method is something that doesn't have to flow in one direction from Question, hypothesis, experiment, observation, to conclusion. Scientific method can take on many forms as long as it ends with fact and an understanding. This understanding comes from knowing how to ask not simply the right question but how to ask a question right then test it to find an

The Scientific Method is the standardized procedure that scientists are supposed to follow when conducting experiments, in order to try to construct a reliable, consistent, and non-arbitrary representation of our surroundings. To follow the Scientific Method is to stick very tightly to a order of experimentation. First, the scientist must observe the phenomenon of interest. Next, the scientist must propose a hypothesis, or idea in which the experiments will be based around. Then, through repeated experimentation, the hypothesis can either be proven false or become a theory. If the hypothesis is proven to be false, the scientist must reformulate his or her ideas and come up with another hypothesis, and the experimentation begins again. This

By testing this hypothesis, you must perform the more improved experiment indoors, all in one day, with multiple trials and adequate breaks in between so that the athlete’s exhaustion and stamina is closer to normal levels. This new experiment still has the same independent variable being the time it takes to run around the lap while the dependent variable are the shoes purchased. Some controlled variables would be the breaks taken between trials which would be done by resting until the athletes stamina is normal and running in an indoor track. Although this is the more improved experiment, there are still extraneous variables that can’t be controlled like starting each trial with the exact exhaustion. This could affect the experiment negatively because her time could’ve theoretically been better with a different type of shoes but this is compensated by having a longer break and running inside to prevent unnecessary fatigue due to possible extreme

There are a variety of threats to internal and external validity when referencing an experiment. Internal validity evaluates the soundness of the procedures in the experiment. It reflects the ability to accurately measure the impact of the independent variable on the dependent variable. Internal threats include history, maturation, selection, testing, reactive measures, instrumentation, regression to the mean, mortality, and diffusion or imitation of treatment.

Having a pretest allows for a check on the randomization procedure. When a pretest is not administered, it is assumed, but not fully verified that the randomization allows the Group C and Group E to start at the same place. Thus, having a pretest could account for the “unhappy randomization”. Finally, preference can be an issue when only a posttest is issued. According to Evaluation in Practice (p. 96), those involved with the experiment may feel more comfortable with a pretest. Additionally, there are possible threats to internal validity that may occur during

Their second study the researchers continued to use a between-subjects design, however using a different sample size of 53 participants. In their first study the researchers found an issue with confederates treating participants differently even if they were not aware of it, so in order to eliminate this experimenters