Stats Final
What is the range of the actual values found in the following set of scores: 1, 4, 0, 20, 5, 40, 47, 21
0 to 47
The animal colony in the psychology department contains 20 male rats (15 blue, 5 spotted) and 30 female rats (15 blue and 15 spotted). 50 total rats.. (30 blue, 20 spotted; 20 male, 30 female). What is the probability of selecting a blue male rat at random?
15 out of 50
The animal colony in the psychology department contains 20 male rats (15 blue, 5 spotted) and 30 female rats (15 blue and 15 spotted). 50 total rats.... (30 blue, 20 spotted; 20 male, 30 female). What is the probability of selecting a blue rat at random?
30 out of 50
The animal colony in the psychology department contains 20 male rats (15 blue, 5 spotted) and 30 female rats (15 blue and 15 spotted). 50 total rats..... (30 blue, 20 spotted; 20 male, 30 female). What is the probability of selecting a female rat at random?
30 out of 50
A curvilinear relationship always has a correlation of +1 or -1.
False
A platykurtic distribution has a more peaked center and fatter tails compared to the normal distribution
False
A scatterplot is not a good way to examine correlation in any way!
False
A statistically significant difference is one that has a high probability of occurring, in other words, it is easy to find and likely to occur.
False
AZ score of O would tell us that 64% of cases scored lower, while 36% of cases scored higher.
False
According to lecture (and most students) Variance values are easier than Standara Deviation values to interpret and explain conceptually.
False
Approximately 95% of cases fall between +1 and -1 standard deviations around the mean.
False
Correlation coefficients based on Z scores are always completely different than those based on Raw Scores.
False
Descriptive Statistics make inferences about larger groups of people from a relatively smaller amount of data.
False
If I flip a coin multiple times, the probability of a head turning up goes down exponentially. For example, on the first flip, the odds of a head are 1/2. On the second flip, the odds of a hard are 1/4. On the third flip, the odd of a head are 1/8. And so on.
False
If you don't know the population standard deviation, even if you know the sample standard deviation, you cannot calculate a confidence interval.
False
In order to be considered a random sample, participants must have an uneven/unequal chance of being selected.
False
Outliers do not effect the value for Standard Deviation at all.
False
Statistically speaking, extreme scores are very probable or likely to occur.
False
The Null Hypothesis states that there is a relation between two variab es or that two means are different.
False
The independent variable is always manipulated by the dependent variable
False
The possible range of a correlation coefficient can be +2 to -2.
False
The standardized normal distribution/curve is a real curve found in the world.
False
This graph is a fair and accurate representation of comparing how many trucks are still on the road for 3 major automobile manufacturers.
False
We could take SAT scores from College Students and make valid inferences about how well an elderly person would do in a nursing home land this person never took the SAT or went to college).
False
When using a sample to calculate an estimation of the population standard deviation, we divide by N, not N-1.
False
An ordinal scale is an example of a continuous measure.
Flase
For Z score calculations of correlation, if we use N-1 in the Denominator for the correlation formula, we must have calculated the Z scores themselves by using a Standard Deviation (SD) calculation based on using N, not N-1.
Flase
If: a) the means of two distributions of scores are equal, and b) the number of scores (N) is equal/the same in each group, then c) a larger standard deviation for one group would indicate less spread/variability among its scores compared to the other group.
Flase
The mean is the only type of average
Flase
A ____distribution is usually the first type of graph that is created to understand and examine the data at hand, a histogram and frequency polygon would come at a later stage of looking at the data.
Frequency
Ordinal is to Nominal as Ratio is to
Interval
We're interested in all of the 12th graders in Muncie. Thus, a group of 50 12th graders from all 12th graders in Muncie would be considered a
Sample
A curve or distribution that is clearly NOT symmetrical is a ____ curve/distribution
Skewed
All multimodal distributions could also be called bimodal.
True
As our sample looks more and more like a population (i.e., the more representative it is), our inferential statistics should be more and more accurate lie., the better they will be in saying something about the population).
True
Correlations can be used to determine how reliable a test is (i.e., you can correlate scores at time 1 and time 2 on a test to determine it's reliability).
True
If we take a sample and imply something about the population, we are using inferential statistics.
True
OGIVE / Cumulative Distribution Graphs are good methods for estimating, but not calculating, percentiles.
True
Sampling with replacement allows for constant probability in terms of chances of being selected for a sample.
True
Standard deviation squared gives you variance.
True
The mean of a sampling distribution of sample means should be close to, if not equal to, the population mean.
True
There are many other types of correlation coefficients you can calculate in addition to Pearson's r depending on what type of data you have.
True
We could expect the percentage of different majors represented in this course (e.g., % of psychology majors) to be about the same as those found in other Psychology 241 (Intro to Stats) courses found on campus at the Ball State University.
True
When using samples, we are depending upon/utilizing inferential statistics to say something about the population.
True
What type of distribution does this BEST depict?
Unimodal
Most statistics that calculate variability (e.g., Standard Deviation/Variance) look at the mean distance scores fall from the
mean
The 3 measures of central tendency to be discussed in this course are
mean, median, and mode
N-1 is to___ as N is to population.
sample
All things being equal, if you RESTRICT, LIMIT, or REDUCE the range of one of the variables (e.g., the I scores) in a correlation equation, the correlation coefficient (r) becomes smaller.
true
Standard deviation is to variance as correlation is to
variance