PSYCH 100A Lecture Notes - Lecture 8: Child Behavior Checklist, Variance, Standard Error
Document Summary
Provides a measure of how well a sample mean approximated a population mean o. We can compute a z-score statistic to compare and o. Remember our sample variability statistics: sample variance s2 , sample standard deviation. Estimate standard error with sample information: standard error estimated standard error, no longer a z-score but now a value called t t will generally be larger than z, because we don"t know. When converting from standard deviation to an estimated standard of error, do not divide by n-1 again; we already corrected for this bias. Even though it"s a sample, divide by n. t distribution is leptokurtic: as we increase our sample size, though, our t distribution starts resembling more closely to the z distribution. Differences between a single group and a known population parameter: if you know , you can compare it to the sample mean, , and see if it is significantly different.
