So I have a table that looks like this
Arrival Time Probability
0 .09
1 .17
2 .27
3 .2
4 .15
5 .12
And I want excel to randomly create one of the 6 arrival time values based on the given probabilities using RAND(). Is there any way to do this other than to have nested If loops?
here's what I came up with.
I would add a column C that calculates the cumulative brackets from 0-1 each digit would represent. If you start with zero and use formulas to calculate your brackets, you can change the probability if needed in the future. (formulas in photo below)
For example, arrival time of 0 would be between 0 and .09.
Then you can use use the rand() function in column D to generate your random number between 0 and 1 and add a lookup function in column E, or wherever you like. Screenshots of the data and formulas:
Replace your probabilities with cumulative probabilities (with a preliminary line for 0) and use VLOOKUP, exploiting the fact that VLOOKUP finds the closest match:
Related
I need a count of how many date items fall within Data 1 & Data 2
ie:
x-1 will have a count of 2
x-2 will have a count of 1
-x-3 will have a count of 2
-y-1 will have a count of 2
What would be the best way to go abouts when approaching this?
Data 1
Data 2
Date
x
1
Date 1
x
1
Date 1
x
1
Date 2
x
2
Date 3
x
2
Date 3
y
1
Date 1
y
1
Date 1
I see only one way to interpret with the available information:
To count the number of times Date_to_test falls within Date_1 and Date_2 (screenshot below, sheet here), you could use either the sum or something like a countifs (with interim calc):
sum approach
=SUM(1*($C$2:$C$11<=$B$2:$B$11)*($A$2:$A$11<=$C$2:$C$11))
countifs + interim calc
helper
=1*(C2<=B2)*(A2<=C2)
(additional column, drag down)
countifs
=COUNTIFS($D$2:$D$11,1)
Screenshot
Alternative
as for the 'sum' approach, sumproduct variants (e.g. =SUMPRODUCT(1*($C$2:$C$11<=$B$2:$B$11),1*($B$2:$B$11>=$A$2:$A$11))) are calculation/memory intensive
despite the countifs + helper approach containing more 'visible' data - these values need only be calculated once, the countifs can then be determined independently (assuming no updates to the helper column) - thus making it more memory/calculation efficient depending upon your calculation mode, screen-updating preferences
Caveat
if, by some misfortune re: interpreting your question, you are referring to some other means of establishing whether "date items fall within Data 1 & Data 2", then without knowing what this is, there very low likelihood of being able to guess this correctly
Number of days before vaccination (x) bacteria count (1000 pieces) (y)
1 112
2 148
3 241
4 363
5 585
I Need to find 2 things
first calculate with growth function third day count and I have been counted.
=GROWTH(I3:I4;H3:H4;H5)
But I need to calculate parameters of growth function( 𝑌=𝑎.𝑏^𝑋)
So how to calculate a and b? I tried to use excel solver but i didn't solve
Seems like LOGEST is designed for what you want:
the LOGEST function calculates an exponential curve that fits your
data and returns an array of values that describes the curve. Because
this function returns an array of values, it must be entered as an
array formula.
Note that there is a difference in how the equation is expressed on an x-y chart with an exponential trendline, and by the function. On the chart, m is expressed as a power of e, so to convert the value returned by the formula to be the same as what is seen on the chart, you would do something like:
=LN(INDEX(LOGEST(known_y,known_x),1))
You are dealing with an exponentional growth, you want to describe. The basic way to handle this, is to take the logarythm of the whole thing, and apply linear regression on that, using the Linest() function.
Suppose I had two time series consisting of weekly data points, and I want to compute the covariance of the time series for the last n weeks using the covariance function in Excel.
Would it be possible to set this scenario up in such a way that a certain cell contains the number of weeks of data I want to compute the covariance for?
That is, changing the cell element to k would lead to the already computed covariance for n weeks to change to the covariance of the data series for the last k weeks?
You decided that sample data was not important so here is some.
date nmbr
03-30-2017 4
04-04-2017 4
04-07-2017 2
04-09-2017 2
04-12-2017 1
04-15-2017 4
04-18-2017 1
04-21-2017 2
04-24-2017 1
04-26-2017 3
04-30-2017 4
05-02-2017 5
05-07-2017 4
05-09-2017 2
05-10-2017 1
05-12-2017 5
05-14-2017 4
My crystal ball tells me that this question is not so much about Excel's COVARIANCE.P or COVARIANCE.S but about limiting date related data. To this end, I'll simply SUM 4 weeks of data.
The formulas needed in E2:H2 (see supplied image) are:
=TODAY()
4
=FLOOR(E2-(F2*7), 7)+1
=SUM(INDEX(B:B, MATCH(G2, A:A)+ISNA(MATCH(G2, A:A, 0))):INDEX(B:B, MATCH(1E+99, A:A)))
Note that the dates are in ascending order.
I am having trouble determining the correct way to calculate a final rank order for four categories. Each of the four metrics make up a higher group. A Top 10 of each category is applied to the respective product to risk analysis.
CURRENT LOGIC - Assignment of 25% max per category.
Columns - Y4
Parts
0.25
25
=IF(L9=1,$Y$4,IF(L9=2,$Y$4*0.9, IF(L9=3,$Y$4*0.8, IF(L9=4,$Y$4*0.7, IF(L9=5,$Y$4*0.6, IF(L9=6,$Y$4*0.5, IF(L9=7,$Y$4*0.4, IF(L9=8,$Y$4*0.3, IF(L9=9,$Y$4*0.2, IF(L9=10,$Y$4*0.1,0))))))))))
DESIRED...
I would like to use a statement to determine three criteria in order to apply a score (1=100, 2=90, 3=80, etc..).
SUM the rank positions of each of the four categories-apply product rank ascending (not including NULL since it's not in the Top 10)
IF a product is identified in more than one metric-apply a significant contribution weight of (*.75),
IF a product has the number 1 rank in any of the four metrics-apply a score of (100).
Data - UPDATED EXAMPLE
(Product) Parts Labor Overhead External Final Score
"XYZ" 3 1 7 7 100
"ABC" NULL 6 NULL 2 100
"LMN" 4 NULL NULL NULL 70
This is way beyond my capability. ANY assistance is appreciated greatly!!!
Jim
I figured this is a good start and I can alter the weight as needed to reflect the reality of the situation.
=AVERAGE(G28:I28)+SUM(G28:I28)*0.25
However, I couldn't figure out how to put a cap on the score of no more than 100 points.
I am still unclear of what exactly you are attempting and if this will work, but how about this simple matrix using an array formula and some conditional formatting.
Array Formula in F2 (make sure to press Ctrl+Shift+Enter when exiting formula edit mode)
=MIN(100,SUM(IF(B2:E2<>"NULL",CHOOSE(B2:E2,100,90,80,70,60,50,40,30,20,10))))
Conditional Formatting defined as shown below.
Red = 100 value where it comes from a 1
Yellow = 100 value where it comes from more than 1 factor, but without a 1.
I'd like to accomplish the following task. There are three columns of data. Column A represents price, where the sum needs to be kept under $100,000. Column B represents a value. Column C represents a name tied to columns A & B.
Out of >100 rows of data, I need to find the highest 8 values in column B while keeping the sum of the prices in column A under $100,000. And then return the 8 names from column C.
Can this be accomplished?
EDIT:
I attempted the Solver solution w/ no luck. 200 rows looks to be the max w/ Solver, and that is what I'm using now. Here are the steps I've taken:
Create a column called rank RANK(B2,$B$2:$B$200) (used column D -- what is the purpose of this?)
Create a column called flag just put in zeroes (used column E)
Create 3 total cells total_price (=SUM(A2:A200)), total_value (=SUM(B2:B200)) and total_flag (=(E2:E200))
Use solver to minimize total_value (shouldn't this be maximize??)
Add constraints -Total_price<=100000 -Total_flag=8 -Flag cells are binary
Using Simplex LP, it simply changes the flags for the first 8 values. However, the total price for the first 8 values is >$100,000 ($140k). I've tried changing some options in the Solver Parameters as well as using different solving methods to no avail. I'd like to post an image of the parameter settings, but don't have enough "reputation".
EDIT #2:
The first 5 rows looks like this, price goes down to ~$6k at the bottom of the table.
Price Value Name Rank Flag
$22,538 42.81905675 Blow, Joe 1 0
$22,427 37.36240932 Doe, Jane 2 0
$17,158 34.12127693 Hall, Cliff 3 0
$16,625 33.97654031 Povich, John 4 0
$15,631 33.58212402 Cow, Holy 5 0
I'll give you the solver solution as a starting point. It involves the creation of some extra columns and total cells. Note solver is limited in the amount of cells it can handle but will work with 100 anyway.
Create a column called rank RANK(B2,$B$2:$B$100)
Create a column called flag just put in zeroes
Create 3 total cells total_price, total_value and total_flag
Use solver to minimize total_value
Add constraints
-Total_price<=100000
-Total_flag=8
-Flag cells are binary
This will flag the rows you want and you can grab the names however you want.