HTH 320 FINAL EXAM QUESTIONS WITH ACCURATE
SOLUTIONS
1) What is Statistics? -- Answer ✔✔ Branch of mathematics used to summarize,
analyze, and interpret a group of numbers or observations
2) What is inferential statistics? -- Answer ✔✔ Procedures used that allow researches
to infer or generalize observations made with samples to the larger population from
which they were selected.
make decisions
3) What is descriptive statistics? -- Answer ✔✔ Procedures used to summarize,
organize and make sense of a set of scores or observations.
Often presented graphically in tables or as summary statistics
4) Define probability -- Answer ✔✔ the frequency of times an outcome occurs divided
by the total number of possible outcomes
5) What two items do you need to know in order to calculate probability? -- Answer
✔✔ 1. The number of possible outcomes - sample space
2. How often the outcome of interest occurs
,6) Probability formula -- Answer ✔✔ p(x) = f(x)/sample space
7) Define normal distribution -- Answer ✔✔ theoretical distribution in which scores
are symmetrically distributed above and below the mean, the median, and the mode
at the center
8) List the characteristics of a normal distribution -- Answer ✔✔ 1. Mathematically
defined
2. theoretical
3. Mean, median, and mode are all located on the 50th percentile
4. symmetrical
5. mean can equal any value
6. SD can equal any positive value
7. total area under curve is 1
8 tails are asymptotic (approach zero but never touch)
9) Define z-scores -- Answer ✔✔ value on the x-axis of a standard normal distribution
10) What is the z-score formula? -- Answer ✔✔ z= x-u/o (population)
or
z= x-M/SD (sample)
11) How do you read the unit normal table? -- Answer ✔✔ column A lists z scores
column B lists the area between a z score and the mean
column C lists the area from a z score toward the tail
12) Define the Central Limit Theorem -- Answer ✔✔ Regardless of the distribution of
scores in a population, the sampling distribution of sample means selected at random
, from that population will approach the shape of a normal distribution, as the number
of samples in the sample distribution increase
13) Define Standard error of mean -- Answer ✔✔ standard deviation of a sampling
distribution of sample means distance that sample mean values deviate from the
value of the population mean
14) Three characteristics of the sample mean -- Answer ✔✔ 1. unbiased estimator
2. a distribution of sample means follows the central limit theorem
3. distribution of sample means has minimum variance
15) Define sampling error -- Answer ✔✔ the extent to which sample means selected
from the same population differ from one another
16) What are some factors that decrease standard error? -- Answer ✔✔ Population
standard deviation decreases
sample size increases
17) In experimental sampling, what are the two specific sampling strategies used? --
Answer ✔✔ 1. Sampling with replacement
2. sampling without replacement
18) What is a population? -- Answer ✔✔ Set of all individuals, items, or data of interest
Group about which scientists will generalize
SOLUTIONS
1) What is Statistics? -- Answer ✔✔ Branch of mathematics used to summarize,
analyze, and interpret a group of numbers or observations
2) What is inferential statistics? -- Answer ✔✔ Procedures used that allow researches
to infer or generalize observations made with samples to the larger population from
which they were selected.
make decisions
3) What is descriptive statistics? -- Answer ✔✔ Procedures used to summarize,
organize and make sense of a set of scores or observations.
Often presented graphically in tables or as summary statistics
4) Define probability -- Answer ✔✔ the frequency of times an outcome occurs divided
by the total number of possible outcomes
5) What two items do you need to know in order to calculate probability? -- Answer
✔✔ 1. The number of possible outcomes - sample space
2. How often the outcome of interest occurs
,6) Probability formula -- Answer ✔✔ p(x) = f(x)/sample space
7) Define normal distribution -- Answer ✔✔ theoretical distribution in which scores
are symmetrically distributed above and below the mean, the median, and the mode
at the center
8) List the characteristics of a normal distribution -- Answer ✔✔ 1. Mathematically
defined
2. theoretical
3. Mean, median, and mode are all located on the 50th percentile
4. symmetrical
5. mean can equal any value
6. SD can equal any positive value
7. total area under curve is 1
8 tails are asymptotic (approach zero but never touch)
9) Define z-scores -- Answer ✔✔ value on the x-axis of a standard normal distribution
10) What is the z-score formula? -- Answer ✔✔ z= x-u/o (population)
or
z= x-M/SD (sample)
11) How do you read the unit normal table? -- Answer ✔✔ column A lists z scores
column B lists the area between a z score and the mean
column C lists the area from a z score toward the tail
12) Define the Central Limit Theorem -- Answer ✔✔ Regardless of the distribution of
scores in a population, the sampling distribution of sample means selected at random
, from that population will approach the shape of a normal distribution, as the number
of samples in the sample distribution increase
13) Define Standard error of mean -- Answer ✔✔ standard deviation of a sampling
distribution of sample means distance that sample mean values deviate from the
value of the population mean
14) Three characteristics of the sample mean -- Answer ✔✔ 1. unbiased estimator
2. a distribution of sample means follows the central limit theorem
3. distribution of sample means has minimum variance
15) Define sampling error -- Answer ✔✔ the extent to which sample means selected
from the same population differ from one another
16) What are some factors that decrease standard error? -- Answer ✔✔ Population
standard deviation decreases
sample size increases
17) In experimental sampling, what are the two specific sampling strategies used? --
Answer ✔✔ 1. Sampling with replacement
2. sampling without replacement
18) What is a population? -- Answer ✔✔ Set of all individuals, items, or data of interest
Group about which scientists will generalize
