Quals- Robinson 1

• the type (positive or negative) and degree of relationship
• between 2 variables. Does not prove causation.

•  average distance that cases within a
• distribution of scores vary from the mean

• these describe individual statistics/test
• scores in relation to the bell curve

• is a graphical representation of a normal distribution. For anything you measure, results across a large population distribute themselves symmetrically. In a normal distribution, the mean median and mode are all equal and the distribution is symmetrical across
• the mean (one half mirrors hte other). The tails are asymptotic in that they come closer and closer to the horizontal axis, but never touch. 68% fall within
• one SD. 95%fall within 2 SD's and 99% fall within 3 SD's. (Internal percentages= 34%, 13.5%, 2%). skewed right=positively skewed and is caused by extreme scores
• at the high end that pull the mean higher than the median (midpoint). skewed left is opposite.

• an expression of an individual score in a way that
• conforms to standard deviation units. For example, 1.5 is one and a half standard deviation units above the mean and -.25 is one-quarter of a standard deviation units below the mean. These are useful in comparing scores across different settings , testing situations and tests.

• o  sometimes called a McCall T is a standard score resulting
• from a z score transformation T= z(10)+50. The advantage= eliminates negative
• numbers or fractions.

arithmatic average. measure of central tendency

• midpoint. the number in the middle of a distribution (15
• numbers, this would be the 8th in order)
• a measure of central tendency

• the most frequently occurring number in a
• distribution.
• measure of central tendency

• distance between highest and lowest
• a measure of  variability

• how far apart numbers are (how spread out they are
• from the mean)

These are found in standardized tests and are a measure of how much observed scores vary from a true score. The smaller the SEM= the more reliable the test.

• shape
• variability

• mean,
• median
• mode

test or measure of the same criteria.

•  is subjective. for example, does the test
• fairly cover what was taught or what experts agree content is appropriate for measurement

•  identifies numerically the relationship between 2 variables (from -1 to 1 with midpoint of 0 that means no
• correlation)

evaluation aimed at guiding the nextinstructional step

results interpreted relative to thesuccess rate of other test takers

results interpreted relative to #of test items  answered correctly,without reference to the success of other test takers.

used to identify strengths and weaknesses of a tool or process so that they might be revised for future use.

aimed at summarizing a segment of achievement (at the end of instruction) (ie, generating a grade or other symbol of achievement)

• how dependable the test is. The consistency
• with which something is accomplished.

• accuracy. Does the test measure what it says it
• measures.

one of three ways to describe a set of scores. Answers the question "How wide are the differences between the scores?" These can include range, standard deviation and variance.