Unbalanced response - ✔✔ Giving more options that are negative than positive options (or vice
versa) which biases the responses towards the more common option
Matched pairs - ✔✔ Grouping two similar subjects and giving different treatments/procedures to
each in order to compare the differences. For example, having one twin take a medication while
the other twin does not.
Population - ✔✔ The entire group you are trying to describe or understand.
Sampling frame - ✔✔ List of group from which you choose your sample.
Sample - ✔✔ The group that is actually picked to be included in a study
Simple random sample - ✔✔ making a selection by following a random pattern and selecting
without replacement. Unbiased.
Systematic sample - ✔✔ Sample is selected by listing the sampling frame, then making a
selection by following a simple pattern (eg. Every 20th name). Unbiased.
, Voluntary sample - ✔✔ Members of the sample may choose not to respond. Similar to Non
Response.
Convenience sample - ✔✔ Participants are easy for researcher to access. Tends to increase bias.
Cluster sample - ✔✔ Sample frame is divided into groups, we select a few groups, then selecting
ALL of the members of those groups.
Stratified sample - ✔✔ Sample frame is divided into groups. Then we choose a random sample
(usually the same size) from within EVERY group.
Histogram - ✔✔ A graphical representation -- bars, measuring the frequency within each interval
Skewed right - ✔✔ Not a symmetric distribution, the tail is on the right
Measures of center - ✔✔ Median, the mean (and mode)
Measures of spread - ✔✔ Range, IQR & standard deviation