basic stat concept

Question 1

what is the purpose of base stat concepts?

Answer 1

• describe the difference between scales
• explain normal distribution and standard deviation
• differentiate the measure of central tendency
• explain validity and reliability

Question 2

what are the types of measurement scales?

Answer 2

• nominal
• ordinal
• interval
• ratio

Question 3

what is the nominal scale?

Answer 3

• qualitative measure.
• named category
• most basic of measurement scales
• only provides info about the difference.

pie chart where you can see what has happened/ your plan. YTD of finances for 12 months.

Question 4

what is ordinal scale?

Answer 4

• qualitative measure.
• no indication of how much better something/ result is, just says its better.
  Ex. medal podium. we know the first place person was better than the second but we don’t know by how much.

Question 5

what is a interval scale?

Answer 5

• quantitative
• scores may be zero.
• tempeture can be measure below zero, so it is a interval scale.

Question 6

what is a ratio scale?

Answer 6

• quantitative.
• there are no zero numbers involved.
• waist to hip ratio, blood pressure.

Question 7

what are the measures of central tendency?

Answer 7

• mean (average)
• median (middle)
• mode (most frequent)

Question 8

what is the mean in stats?

Answer 8

• the arithmetic average of the distribution of scores.
• sensitive to outliers. (only counts the majority)
• used with interval & ratio data

Question 9

what is the median in stats?

Answer 9

• where 50% of the scores are ABOVE and 50% of scores are BELOW.
• when N is odd then the median is the middle score.
• when N is even then the median falls between the two middle scores.

Question 10

what is mode in stats?
what is the mode of 2,4,7,5,9,7,0,1,7,

Answer 10

• the most frequent score in a distribution.
  -7

Question 11

how is variability measured?

Answer 11

• range
• standard deviation

Question 12

how is range measured in variability?

Answer 12

• you take the high of X and subtract it from the low of X
  (H-L=range)

Question 13

why is variability important?

Answer 13

• it is important because you can collect more data and see what is actually happening and if the person is improving.

Question 14

what is standard deviation?

1. if the mean is 10 and SD is 2 (10+/- 2), where will majority of the data fall?

Answer 14

• provides information on the amount of variation or dispersion from the mean.
• tells us how close a set of data is.

1. between 8-12

Question 15

if the data is normally distributed then where should the SD score fall?

Answer 15

• 68%

Question 16

what are correlations?

Answer 16

• numerical co-efficient that indicates the extent to which variables are related.
• r is between -1.00 & 1.00

Question 17

what are 2 examples of correlation?

Answer 17

• Pearsons correlation
• intraclass correlation

Question 18

what is the correlation of the fallowing?
- +1.00
- 1.00
0.00
+/- 0.5-0.7
+/- 0.7-0.8
+/- 0.8 to higher

Answer 18

• perfect positive correlation
• perfect negative correlation
• no correlation
• low correlation
• moderate correlation
• strong correlation

Question 19

what is a perfect positive correlation?

Answer 19

when something else in/decreases then something also in/decreases at the same rate. they move together.

Question 20

what is a perfect negative correlation?

Answer 20

• one variable increases while the other one decreases.
  EX. the longer it takes me to run 1 mile (increase) the lower my VO2 max is (decrease)

Question 21

what is Pearsons correlation?

Answer 21

• used to correlate two different variables.
• only two tests can be measured at the same time.

Question 22

what is validity?

Answer 22

• validity refers to the accuracy of a measurement.
• r should be +/- 0.80 in order to be considered valid.

Question 23

what is reliability?

Answer 23

• reliability refers to the consistency of how we measure.
• if we fallow the exact same procedure will we get the same results.
• r should = +/- 0.90 is considered to be reliable.

Question 24

1. can a test be valid if it is not reliable?
2. can a test be reliable if it not valid?

Answer 24

1. No, a test must be reliable in order for it to be valid. if you are not testing the a certain test the same way then your accuracy (valid) score does not matter.
2. yes, because you are fallowing the repeatable procedure, but if it doesn’t measure the correct test then your not really accomplishing much.