sampling
A type of sampling in which every element in the population being studied has a known chance of being selected for study
what is probability sampling
if a survey is being conducted to support a certain cause, questions are deliberately worded in a biased manner.
what is Deliberate bias
a process of randomly assigning subjects to different treatment groups
what is Randomization
can place into a category but that may not have any logical ordering. For example, you could be categorized as left or right handed.
what are categorial variables
consists of labels or names that cannot be ordered meaningfully, such as categories of hair color, gender, or preferred modes of transportation
what is nominal
a variation of random sampling; the population is divided into subgroups and weighted based on characteristics of the national population
what is stratified sampling
Sometimes questions are worded in such a way that the meaning is misinterpreted by a large percentage of the respondents.
what is Unintentional Bias
Inactive substances, not real medications, that are used to test the effectiveness of drugs.
Placebos
Can be assigned numerical values that indicate how much of the concept is present
what are ordered variables
Ranked in order of preference from highest to lowest, the gaps between the numbers are not identical (e.g. memory test score) (median or mode)
what is ordinal
a sampling technique in which groups of participants that represent the population are used
what is cluster sampling
Most survey respondents have a desire to please the person who is asking the question. They tend to understate their responses about undesirable social habits and opinions, and vice versa.
what is Desire to Please
a technique where the subjects do not know whether they are receiving a treatment or a placebo
what is Blinding
a measurement variable in which it makes sense to talk about differences. Temperature is a good example of an interval variable.
what are Interval-level variables
a type of numerical data where intervals between values are equal but there is no true zero
what is interval
A procedure in which the selected sampling units are spaced regularly throughout the population; that is, every n'th unit is selected.
what is systematic sampling
People do not like to admit that they don’t know what you are talking about when you ask them a question.
what is Asking the Uninformed
an ethical principle that research participants be told enough to enable them to choose whether they wish to participate
what is Informed consent
a meaningful value of zero, and it makes sense to talk about the ratio of one value to another. Pulse rate is a good example.
what are ratio level variables
the comparison of two quantities, true zero
what is ratio
Everyone in the population has an equal chance of being selected, ex: Drawing names from a hat.
what is simple random
If questions are to be understood, they must be kept simple. A question such as “Shouldn’t former drug dealers not be allowed to work in hospitals after they are released from prison?” is sure to lead to confusion.
what is Unnecessary Complexity
participants are followed into the future and events are recorded.
what are prospective studies
can actually count the possible responses. For example, if we measure the number of automobile accidents on a certain stretch of highway, the answer could be 0, 1, 2, 3, and so on.
what are discrete variables