OMIS 1050 WEEK 2

What are statistics?

number collection & analysis & interpretation & presentation science

What are the key statistics elements?

• collect

• analyze

• interpret

• present

What is a population?

all instances

What is a census?

gather population data

What is a sample?

gather subset data

What describes populations?

parameter

What describes samples?

stat

How can one estimate population descriptions?

• choose sample design

• collect

• describe & summarize

What is the population description process?

• sample

• descriptive stat

• infer

What does sampling involve?

collect data

What do descriptive stats involve?

summarize & present data

What does inference involve?

make population probability statement

What is a variable?

characteristic taking on different values

What is a measurement?

process assigning number to variable attribute

What is nominal data?

data measurement

• classified

• no value statement

What is the lowest measurement level?

nominal

What is ordinal data?

data measurement

• ranked

• unequal distance

Which measurements are qualitative?

• nominal

• ordinal

What is interval data?

data measurement

• meaningful distance

What is ratio data?

data measurement

• meaningful distance

• 0 point

Which measurements are qualitative?

• interval

• ratio

What are some nominal data examples?

• colour

• country

What are some ordinal data examples?

• satisfaction

• education

What are some interval data examples?

• IQ

• temperature

What are some ratio data examples?

• money

• distance

• age

What is unstructured data?

data measurement

• no predefined format

• not conventionally analyzed

What are some unstructured data examples?

• media

• image

• audio

• sensor & text data

• mobile & social media activity

What are the 3 most popular data collection methods?

• experiment

• observation

• survey

What is a sampling plan?

sample methodfor selecting a subset of a population to gather data

What is simple random sampling?

sample method

• every item has equal selection chance

• with/out replacement

• obtain from random number table / generator

What is stratified random sampling?

sample method

• stratum division

• simple random sample from stratum

• combine samples

What are strata?

subgroup according to common characteristic

What is systematic sampling?

sample method

• regular interval selection

What is the systematic sampling formula?

k = N/n

What does k stand for in the systematic sampling formula?

interval size

What does N stand for in the systematic sampling formula?

population size

What does n stand for in the systematic sampling formula?

sample size

What is cluster sampling?

sample method

• representative cluster division

• simple random sample from cluster

What are some cluster sampling advantages?

• costly to develop population list

• widely dispersed population

What is a cluster sampling disadvantage?

• more sampling error

  • similar cluster members

What is sampling error?

parameter & stat difference result

What is nonsampling error?

unrelated sampling error

What are some non-sampling errors?

• measurement error

• sample frame error

• coverage error

• process error

• non-response bias

• selection bias

What is measurement error?

non-sampling error

• true value & measured value difference

What is sample frame error?

non-sampling error

• unrepresentative sample list

What is coverage error?

non-sampling error

• certain items can’t be chosen

What is process error?

non-sampling error

• analysis oversight

What is non-response bias?

non-sampling error

• skewed respondent result

What is selection bias?

non-sampling error

• over/under…represented item

What function generates a uniformly distributed decimal between 0 and 1?

=RAND()

What function returns an integer inclusive of the bottom and top numbers?

=RANDBETWEEN

What is an absolute reference?

cell reference staying same if formula’s pasted to other cells

What is a relative reference?

cell reference changing if formula’s pasted to other cells

How does an absolute reference show up?

${row}${column}

What is the absolute reference keyboard shortcut?

Fn + F4

What is the recalculation keyboard shortcut?

Fn + F9

How do you do simple random sampling on Excel?

Data → Data Analysis → Sampling → select “Random” under Sampling Method

How do you do systematic sampling on Excel?

Data → Data Analysis → Sampling → select “Periodic” under Sampling Method

What is defining a named range?

assign name to cell for easy formula reference

What function adds array products?

=SUMPRODUCT

What function returns a set’s max value?

=MAX

What function returns a set’s min value?

=MIN

What function returns a set’s kth value from the maximum?

=LARGE

What function returns a set’s kth value from the minimum?

=SMALL

What function returns a text value from the right?

=RIGHT

What function returns a text value from the left?

=LEFT

What function rounds a number?

=ROUND

What function rounds a number up?

=ROUNDUP

What function rounds a number down?

=ROUNDDOWN

What function returns the set average?

=AVERAGE

What function returns the set median?

=MEDIAN

What function returns the set mode?

=MODE

What function returns the sample set variance?

=VAR.S

What function returns the sample set standard deviation?

=STDEV.S

What function generates the current date?

=TODAY()

What function generates the current date & time?

=NOW()

What function joins multiple cells?

=TEXTJOIN

How do you set up the function that joins multiple cells?

• ignore first 2 fields

• select 1st cell

• IF in-between text, include quotation marks

• select next cell

How do you make columns fit text?

double click between column headings

How do you quickly select a column of cells with values (from the top)?

Shift + Command + Down

How do you quickly select a row of cells with values (from the left)?

Shift + Command + Right

How do you generate a sample descriptive statistic summary?

Data → Data Analysis → Descriptive Statistics → Toggle “Summary statistics”