Under what circumstances is the median or mode a better measure of central tendency than the mean? Explain your response
1. Outliers- the mean is skewed by them. 2. Skewed data- the mean loses its ability to provide the best central location for the data because the skewed data is dragging it away from the typical value
A researcher is studying reading rates in milliseconds per syllable. What scale of measurement?nominal, ordinal, interval, or ratio?is time in milliseconds? Explain your response
Ratio because it has an absolute zero, thus you can compare response time to a zero point in time
True or false- the standard deviation and the range are sensitive to outliers
true- throws the standard deviation off when you have a cluster of data
True or false: The standard deviation can never be 0. Explain your response
False because If the numbers in the data set are equal then there will be no variation from the mean
The Pearson r correlation coefficient is used with ____ level data. Pearson r coefficients can range from __ to __.
Interval; -1; +1.
A researcher is investigating the effects of anxiety on creativity. Individuals with varying levels of anxiety are asked to complete a measure of creativity. The results show a classic U-shaped distribution; that is, individuals with moderate levels of anxiety score the highest on tests of creativity. Individuals with very low or very high levels of anxiety score much lower on tests of creativity. Would the Pearson r correlation coefficient be a good statistic to use in this case? Explain your response
No because levels of anxiety are measured on a ordinal scale- ex: low/medium/high. Creativity test scores are measured on a nominal scale because you assign a number to distinguish the test scores
An experimenter is examining the relationship between age and self-disclosure. A large sample of participants that are 25 to 35 years old and participants that are 65 to 75 years old are compared, and significant differences are found with younger participants disclosing much more than older people. The researcher reports an effect size of .34. What does this mean
the effect size is the mean of the experimental group (young)-the mean of the control group (old)/the standard deviation, meaning that younger people are 34% more likely to self-disclose than older people
what is an outlier?
doesn't follow the normal data, shifts the normal curve to what side it falls on
What is the Hawthorne Effect
an effect in which participants perform better under observation
what is the definition of variables in terms of the techniques the researcher uses to measure
what does it mean when you reject the null hypothesis
When results are statistically significant
what is reliability?
when you can repeat an experiment
what is the difference between ratio and interval data
Interval data does not include the absolute zero
what is validity?
the extent to which instruments measure what they're intended to measure
what is quantitative methodology
it has numbers to measure
what is positive and negative correlation
What is nominal measurement?
names, categories, can be coded but not measured
What is ordinal measurement?
rankings, can be counted and ordered but not measured
What is interval measurement?
no absolute zero, like a temperature
What is ratio measurement?
such as age, weight, height, or percentage
What is an independent variable?
presumed cause, controlled and manipulated by experimenter
What is a dependent variable?
presumed effect, observed or measured for variation as a primed result of the variation in the IV
What is a control variable?
portion that isn't being experimented on
What is an extraneous variable?
undesirable variables that influence the relationship between the variables that the experimenter is examining. Not part of the experimental situation
What is a confounding variable?
extraneous variable whose presence affects the variables being studied so that the results you get do not reflect the actual relationship between the variables under investigation. Part of the experimental situation
What is reliability?
the extent to which data findings are able to be repeated. Predictable, endure over time, similar results found
What is internal consistency?
When all parts measure the same
What is internal validity?
how much of the changes in the DV were due to something in the research, and not something in-related: history, maturation, testing, Hawthorne effect (how someone acts when they know they're being observed)
What is external validity?
how well to research findings generalize Population Validity and Ecological Validity
Want to see the other 29 Flashcards in 1st quiz?JOIN TODAY FOR FREE!