Describe the characteristics of nonexperitmental research. 

1. nonrandom sampling – can be intact or volunteer
2. small ample sizes, less than 30
3. nominal or ordinal levels of measurement
4. population is not known to be normally distributedtypes of study – survey, correlation, decriptive, or historical
answers “what is” or “what was” 

Describe nominal, ordinal and interval level scales of measurement. 

interval level scale measures in equal increments
nominal level scale counts or tabulates the number of occurences within a classification
ordinal level scale places variables in rank order 

How do you select an inferential test of significance for an experimental and a correlation research study? 

Determine whether a parametric or nonparametric test of significance is needed:
TRUE
Parametric Assumptions
1. use tests of high validity and reliability
2. must have interval level of measurement
3. must be over 30 subjects
4. population is known to be normally distributed
5. scores of pre/post standardized tests must be normall distributed
6. set level of significance
QUASI
Nonparametric assumptions
1. use tests of high validity and reliability
2. must have nominal or ordinal level measurement
3. samples are often nonrandom
4. sample sizes are small – less than 30
5. population are not known to be normally distributed
6. set level of significance
Once the test category is determined, select an appropriate statistical test. 

Describe the words reliabilty and validity as they relate to research 

reliability – how accurately and consistently a test measures from one administration to the next administration of the test on the same population. Reliable tests yield similar scores between administrations
validity – how well do the items on a test measure what they are supposed to measure 

Describe a variable and its use in research. 

a variable is a trait or object that must be able to change and be measurable. 

Describe the difference between a research question and a hypothesis 

research question – states the problem and gives the interaction between the variables
hypothesis – gives additional information such as testing materials, period of tiem and how the sample was selected 

Describe the relationship between independent and dependent variables 

independent variable is the treatment
dependent variable is the change brought about by the treatment 

Describe the difference between internal and external validity 

internal validity represents controls to secure the integrity or deal with the threats of the study. The seven threats are: time, loss of subjects, maturation, selection errors, testing, changes in measurement and statistical regression
external validity – the ability to generalize the results of the study back to the population it represnts 

Describe the difference between a research hypothesis and a null hypothesis 

research hypothesis states that there will be a statistically significant difference or relationship between variables
null hypothesis states that there will be no significant difference or relationship between variables. If there is a significant difference, the null hypothesis is rejected. 

Describe an experimental group and a control group 

experimental group receives a particular treatment. Dependent variable that is expected to change.
control group independent variable – receives no treatment or a different treatment and should not be contaminated 

Describe the characteristics of experimental research 

use parametric assumptions
1. random sampling
2. larger population – sample of 30 or more
3. uses an experimental and control group
4. interval measurements
5. population is known to be normally distributed 

Describe the difference between quantitative and qualitative research 

quantitative – exact mathematical value so difference between 2 or more variables is statistically analyzed for significance
qualitative – classifying by using word descriptions to determeine value, rank or position of a variable under study 

Describe the difference between a popluation and a sample 

a population is a whole group with its own characteristics and varies in size
a sample is a representative portion of a defined population 

Describe the difference between random sampling and intact group 

intact group – entire population, can be volunteer
random sampling – a group that is chosen randomly to represent the popluation. Each individual in the population has an equal chance of being selected 

Describe the word siginificant as it relates to research 

Decide if there is a significant difference between the experimental group and the control group using an inferential test of significance at a predetermined level. In education, an alpha level of significance (.05) is often used. 

Describe the difference between a research article and an opinion article 

Opinion articles are subjective – they express the beliefs, speculations or evaluations or the author of other sources consulted
research is objective and does not show biases of the person doing the research 

Decribe the difference between descriptive statistics and inferential statistics 

descriptive statistics uses percentages, averages, frequency distributions and measures of central tendency to describe and identify the characteristics of variables of groups under study
inferential statistics primarily deals with the question: is the difference or relationship between vairables great enough to rule out chance factors as having produced a difference or relationship 
