Collecting Data Vocab
Every person or object of interest in a study
What is a population?
We must __________ aspects of the experiment that we believe will effect response
What is control?
Occurs when a sample is composed of volunteers, who may differ from individuals who don’t choose to volunteer.
What is Voluntary response bias?
A study in Malindi, Kenya, was undertaken to determine if a relationship existed between the water drainage and mosquito population in different areas of the city. Using GPS, the city was overlaid with a map containing 50 grid cells. Ten of the cells that contained standing water, and ten of the cells with good water drainage were randomly selected and the mosquito population was estimated for each cell. What type of study was conducted, and what is the response variable?
What is an observational study was conducted, and the response variable is the mosquito population?
Why do we sample?
To take the data we collect and analyze it in order to make a conclusion/inference.
The control treatment used in medical experiments.
What is a placebo?
When the sample is the entire population, we call this a _______________
What is a census?
When survey questions are confusing or leading.
What is Question wording bias?
Café Beignet Canal in New Orleans offered a new breakfast item on the menu for one week. For the entire week, every customer who ordered the new breakfast item was asked to rate it on a scale of 1 to 5. What type of study was conducted, and what is the response variable?
What is an observational study was conducted, and the response variable is the rating on the 1-to-5 scale?
Sampling every nth person in a convenient location. Ex. first 10 students to show up to school.
What is Convenience Sampling?
When you randomly pick a starting point on a list and select every 5th person thereafter
What is Systematic Sampling?
When you can't determine which variable is effecting the difference in the outcomes of an experiment, then the variables are ______
What is counfounded?
When a significant number of participants do not return their surveys. This could result in bias
What is Nonresponse bias?
A website designer is interested in the relationship between the shade of blue of an online advertisement and the click-through rate. The click-through rate is calculated by dividing the number of clicks that an advertisement receives by the number of times the advertisement is viewed. The designer randomly assigns 80 volunteers to one of four advertisements, each with a different shade of blue, and calculates the click-through rate for each advertisement. What type of study was conducted, and what is the response variable?
What is an experiment was conducted, and the response variable is the click-through rate?
randomly determine the sample through narrowing down the pop in several random steps. Ex. County - Town - Street
What is Multistage sampling?
When entire groups, which are representative of the population are chosen randomly for a survey.
What is Cluster Sampling?
The variables that are manipulated in an experiment are called the _______
What is a factor?
When individuals inaccurately report their own traits.
What is Self-reported response bias?
A study released in the Journal of the National Cancer Institute followed a group of 4,937 subjects over 32 years. The study found a strong association between alcohol consumption and lung cancer. Subjects who consumed more than 24 grams of alcohol per day were more than three times as likely to develop lung cancer than subjects who did not drink alcohol. Identify the explanatory and response variables in the study.
What is...
explanatory variable: alcohol consumption
response variable: lung cancer
A large simple random sample of people aged nineteen to thirty living in the state of Colorado was surveyed to determine which of two smartphones just developed by a new company was preferred. To which of the following populations can the results of this survey be safely generalized?
What is the only people aged nineteen to thirty living in the state of Colorado?
In this experimental design, you first divide the participants into groups based on a variable or characteristic that you believe will affect the response. Then you randomly assign to subjects from each group to treatments.
What is Randomized Blocking Design?
The participants assigned to a baseline treatment level (not necessarily no treatment) used for comparison purposes in an experiment are the _______________________.
What is a Control Group
occurs when certain segments of a population are inadequately represented in a sample, leading to skewed or inaccurate results.
What is Undercoverage bias?
A study released by researchers at Massachusetts General Hospital (MGH) looked at data from a population of over 30,000 adults over the course of 10 years. The study found a strong association between long-term consumption of ultra-processed foods (UPFs) foods altered with additives and preservatives – and stroke. Subjects who consumed increased amounts of UPFs were 9% more likely to have a stroke than subjects who did not consume increased amounts of UPFs. Identify the explanatory and response variables in the study.
What is...
explanatory variable: consumption of ultra-processed foods
response variable: incidence of stroke
#1 Control
#2 Randomization
#3 Replication
What is the Principles of Experimental Design?