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A measure of how far data values typically are from the mean.
What is variability?
Variance is always this type of number (positive, negative, or zero?).
What is non-negative?
A smaller group selected from a larger population.
What is a sample?
Chi-square values are always this (positive or negative?).
What is positive?
This distribution is symmetric and bell-shaped.
What is the normal distribution?
The difference between the largest and smallest values in a dataset.
What is the range?
We square deviations mainly to eliminate this issue.
What is negative values canceling positive ones?
The process of using sample data to estimate a population value.
What is statistical inference?
Chi-square distributions are typically skewed in this direction.
What is right-skewed?
This distribution is skewed and only takes positive values.
What is the chi-square distribution?
This measure of spread uses squared deviations from the mean.
What is variance?
This symbol represents population variance.
What is σ² (sigma squared)?
When different samples give different results, this is called…
What is sampling variability?
This determines the shape of a chi-square distribution.
What are degrees of freedom?
As degrees of freedom increase, chi-square distributions become more like this.
What is normal (less skewed)?
This is the square root of variance and is in the same units as the data.
What is standard deviation?
This symbol represents sample variance.
What is s²?
The larger the sample size, the variability of estimates tends to…
What is decrease?
Degrees of freedom for variance estimation are calculated as…
What is n − 1?
Small degrees of freedom produce a graph that is very…
What is skewed right?
When data points are very spread out, this value is relatively…
What is large variance?
When we divide by (n−1) instead of n, we are correcting for this.
What is bias in estimating population variance?
This distribution helps estimate population variance from a sample. Hint: It is the next section we are covering.
What is the chi-square distribution?
We use chi-square distributions specifically when working with this parameter.
What is population variance (σ²)?
This is what the horizontal axis represents in a chi-square graph.
What are chi-square values?