Statistics

Front 1

what is the explanatory variable

Back 1

variable that you control

Front 2

what is the response variable

Back 2

its the one you are measuring
it is the one that changes asthe result of the explanatory variable you control

Front 3

what are extraneous variables

Back 3

they are other variables that could affect your experiment and you must keep them the same or constant so they dont affect your results

Front 4

where can experiments be completed

Back 4

in a laboratory, as a field experiment, as a natural experiment

Front 5

what are laboratory experiments

Back 5

they are done in a lab uts easier to control the explanatory and extraneous variables as you feel confident any changes in the response variable are dueto the explanatory variable

Front 6

what are field experiments

Back 6

are carried out in a natural environment and you have less controlkver theextranerous variables like weather than you have in a lab but you get results which are valid for the real world you use this if a lab isnt practical

Front 7

what is a natural experiment

Back 7

cannot control the explanterory variable or keep it constant and we just look at how existing values affect the response variable you could do this for collecting data from thereal world about overweight people and heart disease but you are not cpntrolling theweight bjt can collect data for different weights and moniter overweight people you have lirtle control over the extranerois variables

Front 8

what are control groups

Back 8

its when you have a grouo of peoole who you telkare all taking part in the experiment but half of them you use and half you give something fake and compare the resultsto seeif the sjbstance does what kts meant to doto only kne group its ab commonly used for testing drugs the experimental group is giventhe drug all the extranerous variables are kept the same

Front 9

what should be considered to make it a fair test?

Back 9

to make the experiment reliable
take measurements at a fair point as in domt take the measurements straight awaylet them warmup or adjust etc
you shoukd take several measurements and then work out the average to make your results reliable
check data for rogue values - outliners values that are measures incorrectly so are too large or too small so try measure it again and ignore outliners astheymay affectyour results
if more than 1 person measures something you can get interobserver bias whichcould affect your results

Front 10

what is inter observer bias

Back 10

differentpeople measure the results differently so all recorders need clear guidlines in which to record the results and they need to record and comparetheir results tomakesurethey are tge same

Front 11

wjat are the 3 rules to avoid inter observer bias

Back 11

the recordersshould have training first
they should do a trial run first
they should agree the rules first for what they do and dont record

Front 12

for eachof the followingare they leading ambiguous or neither
you dont like me do you
how many hours do you spend on the internet eachweek
do you slend a lotof moneyon christmas presents
reality programmes are rubbish arent they

Back 12

leading
neither
ambiguous
leading

Front 13

what are 4 ways tocarry outa questionnaire

Back 13

phone interview
faceinterview
postal questionnaire
internet sites

Front 14

describe and include ad and disad of face to face interviews

Back 14

higher response rate,immediate response, getmore honest answers, explain questions and you know your sample has answered the question
can be time consuming as you can only do one person at a time can be expensive to carry out and cants cover arange of places, some people may be embarrassed so lie

Front 15

ad and disad of phone interviews

Back 15

same as face to face but less time consuming and cancover a larger geographical area its also cheaper

Front 16

ad and disad of postal questionaires

Back 16

its cheaper than the previous 2 methods, can be sent out to a
arger geographical area and less time consuming, they can fill outthe survey and a time that suits them
cant be certain the right type of peraon is completing the survey there isn't a very high response rate so may need toadd an incentive

Front 17

ad and disad of online survey

Back 17

same as postal they rae cheaper and can cover a large area
low response rate, not everyone has a computer and dont know whos completed it

Front 18

what should you always do before a survey

Back 18

always do a pilot study to check the range of answers you will get and sort out any problems for example answer boxes before you startyour real survey

Front 19

what is convenience sampling

Back 19

chosen for ease and convinience and isnt random

Front 20

explain method and ads and disad of convinience sampling

Back 20

selection of population is chosen at one particular time and one particulra place for example standing in town and asking the first 20 people who walk past
ad-you domt need a list of the popukation, it can be completed atany time or place that suits the interviewer
disad- can be very bias, no attempt is made to make the sample represent your popukation

Front 21

what is cluster sampling

Back 21

for example a school and divide it into 5 cluster 1 for each year and lable each year 1- 5 then roll a dice ignoring 6 and ask every girl in that year group or mcdonalds want to know what mcflurry flavour they could divide their cluster by stores so eachstore is a cluster and the customers at the store are the sample then chooose a certain amount of stores and record the people from them over a period of time
ad- saves alot of time on travelling if your popukation is spread over a wide area as you only go to a few , its more convinient than a random sample over the whole population, itcan be cheaper
disad- could be biased as road for example are wealtjiers that other roads in population and 1 year group in stmafys doesng represent the school

Front 22

what is quotasampling and ads and disads

Back 22

often used for market reasearch you aresplit into grouos based on age, gender, social or economical backround the intervieweris toldto interview a certain number of people from each group
ads- quick to usefor example interview people in their 20s
disad - sample can be biased as you choose who you interview

Front 23

what is standardising scores

Back 23

they are used to compare values from different sets of data when the sets of data are different size and spread

Front 24

what is stimulating situations

Back 24

sometimes we use random numbers to stimulate situations for expample a buisness might want to stimulate how many different types of call come into their call centre
you split what you wnat to record into different catagories and use data already recorded to get these into porportions just like a stratified sample
allocate each catagory a number or more than 1 to be in porportion which could be a score on a die or set of numbers in porportion to the values you have that you can get using a random number table
role a dice or use a random number table to stimulate how often these catagories willcome up
you need to get the numbers you allocate in porportion to the data you will be given at the beginning of the question and then use the rolled dice values given or the random number table given to list which catagories these go with very similar to random sampling